with free intervals (instead of fixed free headers) we need to check `improved_by` from extension code

make FreeHeadersRemaining an Option => we know that when we are outside of tx body, it is `None` and otherwise it is `Some`

added WeightInfoExt for pallet-bridge-grandpa to include extra wight coming from CheckAndBoostBridgeGrandpaTransactions

added CheckAndBoostBridgeGrandpaTransactions that checks whether bridge GRANDPA transactions are obsolete and, if not, it may apply priority boost to

check_obsolete_submit_finality_proof may now boost transaction priority (this is not used yet - see next commit)

move grandpa call result check from RefundTransactionExtensionAdapter to RefundBridgedGrandpaMessages

added is_free_execution_expected parameter to the submit_finality_proof_ex + check it from the transaction extension

Bumps [strum](https://github.com/Peternator7/strum) from 0.26.1 to 0.26.2.
- [Release notes](https://github.com/Peternator7/strum/releases)
- [Changelog](https://github.com/Peternator7/strum/blob/master/CHANGELOG.md)
- [Commits](https://github.com/Peternator7/strum/commits)

---
updated-dependencies:
- dependency-name: strum
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>