build(deps-dev): bump hardhat-gas-reporter from 1.0.4 to 1.0.8

Bumps [hardhat-gas-reporter](https://github.com/cgewecke/hardhat-gas-reporter) from 1.0.4 to 1.0.8.
- [Release notes](https://github.com/cgewecke/hardhat-gas-reporter/releases)
- [Changelog](https://github.com/cgewecke/hardhat-gas-reporter/blob/master/CHANGELOG.md)
- [Commits](cgewecke/hardhat-gas-reporter@v1.0.4...v1.0.8)

---
updated-dependencies:
- dependency-name: hardhat-gas-reporter
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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Author: dependabot[bot]