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/utils/binary-merkle-tree/Cargo.toml

@@ -20,6 +20,6 @@ sp-core = { path = "../../primitives/core" }
 sp-runtime = { path = "../../primitives/runtime" }
 
 [features]
-debug = [ "array-bytes", "log" ]
-default = [ "debug", "std" ]
-std = [ "hash-db/std", "log/std", "sp-core/std", "sp-runtime/std" ]
+debug = ["array-bytes", "log"]
+default = ["debug", "std"]
+std = ["hash-db/std", "log/std", "sp-core/std", "sp-runtime/std"]