Resolve "Display and logic improvements for cycle analytics"

What does this MR do?

Goal of this MR is to fix different problems with SQL queries connected with cycle analytics. Here is a detailed description of changes for each step:

1. Issue stage: counting into the median and showing as events only issues that already have milestone attached or been added to the board. They do not need to have associated MR.
2. Plan stage: counting into the median and showing as events only issues that already have milestone attached or been added to the board and has associated commit. They do not need to have associated MR.
3. Code stage: We count into the median and show as events only merge requests that have closing issue pattern and there was a commit associated with an issue mentioned in the MR.
4. Test stage: no changes.
5. Review stage: We count into the median and show as events only merge requests that have closing issue pattern and have been merged.
6. Staging stage: We count into the median only merge requests that have closing issue pattern. We show deployed jobs. (No change here).
7. Production stage: We count into the median and show as events only issues with milestones, that have been deployed to production.

cc @valexieva

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Performance and testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Closes #30138 (closed)

EE backport: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/14143