Create Ci::DailyBuildGroupReportResult for daily code coverage

What does this MR do?

This basically moves away from the EAV model which was Ci::DailyReportResult. Process is still the same, but now we're using JSONB column to store all the metrics. For now, it's just coverage.

This is based on #212646 (comment 326296664).

The old ci_daily_report_results table will be removed next release on #214848 (closed) to follow our guidelines for dropping a table.

Also, I removed the old worker Ci::DailyReportResultsWorker. Given 13.0 is a major release, this is fine according to our guidelines.

Solves #212646 (closed)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability 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
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

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