Enforce consistent and correct toml formatting (#2518)

Using taplo, fixes all our broken and inconsistent toml formatting and
adds CI to keep them tidy.

If people want we can customise the format rules as described here
https://taplo.tamasfe.dev/configuration/formatter-options.html

@ggwpez, I suggest zepter is used only for checking features are
propagated, and leave formatting for taplo to avoid duplicate work and
conflicts.

TODO
- [x] Use `exclude = [...]` syntax in taplo file to ignore zombienet
tests instead of deleting the dir

---------

Signed-off-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>
Co-authored-by: Bastian Köcher <git@kchr.de>

substrate/primitives/api/proc-macro/Cargo.toml

@@ -17,7 +17,7 @@ proc-macro = true
 
 [dependencies]
 quote = "1.0.28"
-syn = { version = "2.0.38", features = ["full", "fold", "extra-traits", "visit"] }
+syn = { version = "2.0.38", features = ["extra-traits", "fold", "full", "visit"] }
 proc-macro2 = "1.0.56"
 blake2 = { version = "0.10.4", default-features = false }
 proc-macro-crate = "1.1.3"
@@ -29,7 +29,7 @@ assert_matches = "1.3.0"
 
 [features]
 # Required for the doc tests
-default = [ "std" ]
-std = [ "blake2/std" ]
+default = ["std"]
+std = ["blake2/std"]
 no-metadata-docs = []
 frame-metadata = []