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.~~

substrate/primitives/trie/src/cache/mod.rs

@@ -323,7 +323,7 @@ type ValueAccessSet =
 ///
 /// This cache should be used per state instance created by the backend. One state instance is
 /// referring to the state of one block. It will cache all the accesses that are done to the state
-/// which could not be fullfilled by the [`SharedTrieCache`]. These locally cached items are merged
+/// which could not be fulfilled by the [`SharedTrieCache`]. These locally cached items are merged
 /// back to the shared trie cache when this instance is dropped.
 ///
 /// When using [`Self::as_trie_db_cache`] or [`Self::as_trie_db_mut_cache`], it will lock Mutexes.

substrate/primitives/trie/src/lib.rs

@@ -326,7 +326,7 @@ pub fn read_trie_value<L: TrieLayout, DB: hash_db::HashDBRef<L::Hash, trie_db::D
 
 /// Read the [`trie_db::MerkleValue`] of the node that is the closest descendant for
 /// the provided key.
-pub fn read_trie_first_descedant_value<L: TrieLayout, DB>(
+pub fn read_trie_first_descendant_value<L: TrieLayout, DB>(
 	db: &DB,
 	root: &TrieHash<L>,
 	key: &[u8],
@@ -447,7 +447,7 @@ where
 
 /// Read the [`trie_db::MerkleValue`] of the node that is the closest descendant for
 /// the provided child key.
-pub fn read_child_trie_first_descedant_value<L: TrieConfiguration, DB>(
+pub fn read_child_trie_first_descendant_value<L: TrieConfiguration, DB>(
 	keyspace: &[u8],
 	db: &DB,
 	root: &TrieHash<L>,