Fix codeowners (#2444)

## Problem

In the last PR we saw that the global code owners permissions was not
working when a PR have modifications on a folder with specific
codeowners.

## Diagnostic and solution

The problem is that the `CODEOWNERS` file doesn't have any inheritance
and take the latest rule in the file as the code owner. Sources :
https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-code-owners#example-of-a-codeowners-file
/
https://stackoverflow.com/questions/73398405/does-codeowners-inherit-owners

So if a modification was done in TxPool then the TxPool (that is the
last one) will override all of the precedent one. The only solution we
have to have the behavior we want is to re-add the global code owners on
the specific rules too.

## Checklist
- [x] Breaking changes are clearly marked as such in the PR description
and changelog
- [x] New behavior is reflected in tests
- [x] [The specification](https://github.com/FuelLabs/fuel-specs/)
matches the implemented behavior (link update PR if changes are needed)

### Before requesting review
- [x] I have reviewed the code myself
- [x] I have created follow-up issues caused by this PR and linked them
here

.github/CODEOWNERS

@@ -2,7 +2,7 @@
 * @xgreenx @Dentosal @MitchTurner
 
 # Code owners for the gas price algorithm
-crates/fuel-gas-price-algorithm @MitchTurner @rafal-ch
+crates/fuel-gas-price-algorithm @xgreenx @Dentosal @MitchTurner @rafal-ch
 
 # Code owners for the transaction pool
-crates/services/txpool_v2 @AurelienFT
+crates/services/txpool_v2 @xgreenx @Dentosal @MitchTurner @AurelienFT