Remove dependency between check and jacocoMergedReport

[BraisGabin]

jacocoMergedReport is in the critical path of my builds:
https://ge.detekt.dev/s/24zl4n3tj746e/timeline?details=j2hxxhlnrx3wg&show-only-critical-path
https://ge.detekt.dev/s/ok5dejkm7eo34/timeline?details=j2hxxhlnrx3wg&show-only-critical-path

But its output is not relevant. The only place where it is relevant is in the workflow codecoverage.yaml. But there we don't execute it using check we execute it using its name.

[codecov]

Codecov Report

Merging #5846 (e1b10bd) into main (b8c0aaa) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main    #5846   +/-   ##
=========================================
  Coverage     84.56%   84.56%           
  Complexity     3785     3785           
=========================================
  Files           546      546           
  Lines         12936    12936           
  Branches       2275     2275           
=========================================
  Hits          10939    10939           
  Misses          863      863           
  Partials       1134     1134           

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[3flex]

its output is not relevant

Just FYI there's an aggregated HTML report generated by the report aggregation task, so it's not only used by Codecov.

But reading the definition of check from Gradle docs it says that verification tasks should be attached, but this isn't a verification task as such, so it makes sense to drop it.