Fix spelling mistakes across the whole repository (#3808)

**Update:** Pushed additional changes based on the review comments.

**This pull request fixes various spelling mistakes in this
repository.**

Most of the changes are contained in the first **3** commits:

- `Fix spelling mistakes in comments and docs`

- `Fix spelling mistakes in test names`

- `Fix spelling mistakes in error messages, panic messages, logs and
tracing`

Other source code spelling mistakes are separated into individual
commits for easier reviewing:

- `Fix the spelling of 'authority'`

- `Fix the spelling of 'REASONABLE_HEADERS_IN_JUSTIFICATION_ANCESTRY'`

- `Fix the spelling of 'prev_enqueud_messages'`

- `Fix the spelling of 'endpoint'`

- `Fix the spelling of 'children'`

- `Fix the spelling of 'PenpalSiblingSovereignAccount'`

- `Fix the spelling of 'PenpalSudoAccount'`

- `Fix the spelling of 'insufficient'`

- `Fix the spelling of 'PalletXcmExtrinsicsBenchmark'`

- `Fix the spelling of 'subtracted'`

- `Fix the spelling of 'CandidatePendingAvailability'`

- `Fix the spelling of 'exclusive'`

- `Fix the spelling of 'until'`

- `Fix the spelling of 'discriminator'`

- `Fix the spelling of 'nonexistent'`

- `Fix the spelling of 'subsystem'`

- `Fix the spelling of 'indices'`

- `Fix the spelling of 'committed'`

- `Fix the spelling of 'topology'`

- `Fix the spelling of 'response'`

- `Fix the spelling of 'beneficiary'`

- `Fix the spelling of 'formatted'`

- `Fix the spelling of 'UNKNOWN_PROOF_REQUEST'`

- `Fix the spelling of 'succeeded'`

- `Fix the spelling of 'reopened'`

- `Fix the spelling of 'proposer'`

- `Fix the spelling of 'InstantiationNonce'`

- `Fix the spelling of 'depositor'`

- `Fix the spelling of 'expiration'`

- `Fix the spelling of 'phantom'`

- `Fix the spelling of 'AggregatedKeyValue'`

- `Fix the spelling of 'randomness'`

- `Fix the spelling of 'defendant'`

- `Fix the spelling of 'AquaticMammal'`

- `Fix the spelling of 'transactions'`

- `Fix the spelling of 'PassingTracingSubscriber'`

- `Fix the spelling of 'TxSignaturePayload'`

- `Fix the spelling of 'versioning'`

- `Fix the spelling of 'descendant'`

- `Fix the spelling of 'overridden'`

- `Fix the spelling of 'network'`

Let me know if this structure is adequate.

**Note:** The usage of the words `Merkle`, `Merkelize`, `Merklization`,
`Merkelization`, `Merkleization`, is somewhat inconsistent but I left it
as it is.

~~**Note:** In some places the term `Receival` is used to refer to
message reception, IMO `Reception` is the correct word here, but I left
it as it is.~~

~~**Note:** In some places the term `Overlayed` is used instead of the
more acceptable version `Overlaid` but I also left it as it is.~~

~~**Note:** In some places the term `Applyable` is used instead of the
correct version `Applicable` but I also left it as it is.~~

**Note:** Some usage of British vs American english e.g. `judgement` vs
`judgment`, `initialise` vs `initialize`, `optimise` vs `optimize` etc.
are both present in different places, but I suppose that's
understandable given the number of contributors.

~~**Note:** There is a spelling mistake in `.github/CODEOWNERS` but it
triggers errors in CI when I make changes to it, so I left it as it
is.~~

cumulus/client/pov-recovery/src/lib.rs

@@ -18,7 +18,7 @@
 //!
 //! A parachain needs to build PoVs that are send to the relay chain to progress. These PoVs are
 //! erasure encoded and one piece of it is stored by each relay chain validator. As the relay chain
-//! decides on which PoV per parachain to include and thus, to progess the parachain it can happen
+//! decides on which PoV per parachain to include and thus, to progress the parachain it can happen
 //! that the block corresponding to this PoV isn't propagated in the parachain network. This can
 //! have several reasons, either a malicious collator that managed to include its own PoV and
 //! doesn't want to share it with the rest of the network or maybe a collator went down before it
@@ -338,8 +338,8 @@ where
 		let mut blocks_to_delete = vec![hash];
 
 		while let Some(delete) = blocks_to_delete.pop() {
-			if let Some(childs) = self.waiting_for_parent.remove(&delete) {
-				blocks_to_delete.extend(childs.iter().map(BlockT::hash));
+			if let Some(children) = self.waiting_for_parent.remove(&delete) {
+				blocks_to_delete.extend(children.iter().map(BlockT::hash));
 			}
 		}
 		self.clear_waiting_recovery(&hash);
@@ -448,7 +448,7 @@ where
 
 	/// Import the given `block`.
 	///
-	/// This will also recursivley drain `waiting_for_parent` and import them as well.
+	/// This will also recursively drain `waiting_for_parent` and import them as well.
 	fn import_block(&mut self, block: Block) {
 		let mut blocks = VecDeque::new();
 
@@ -495,7 +495,7 @@ where
 					tracing::debug!(
 						target: LOG_TARGET,
 						block_hash = ?hash,
-						"Cound not recover. Block was never announced as candidate"
+						"Could not recover. Block was never announced as candidate"
 					);
 					return
 				},