chore: Introduce logql/syntax go module

[cyriltovena]

What this PR does / why we need it:

This PR introduce a new set of go modules but mainly logql/syntax so it can be pulled by other project without vendoring the whole Loki.

Which issue(s) this PR fixes: Fixes #

Special notes for your reviewer:

Checklist

• [x] Reviewed the CONTRIBUTING.md guide (required)
• [x] Documentation added
• [x] Tests updated
• [x] Title matches the required conventional commits format, see here
  • Note that Promtail is considered to be feature complete, and future development for logs collection will be in Grafana Alloy. As such, feat PRs are unlikely to be accepted unless a case can be made for the feature actually being a bug fix to existing behavior.
• [x] Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
• [x] If the change is deprecating or removing a configuration option, update the deprecated-config.yaml and deleted-config.yaml files respectively in the tools/deprecated-config-checker directory. Example PR

[cyriltovena]

That is wild the test is failing because of a different rounding

Going to downgrade prometheus.