runtime.jvm.gc.count metric reports invalid unit "collections"

[PeterF778]

Describe the bug
Garbage Collection metric runtime.jvm.gc.count reports the unit as "collections", which is an invalid unit.

Steps to reproduce
Enable GC metrics by specifying -Dotel.instrumentation.runtime-metrics.experimental-metrics.enabled=true on the java command line with the agent. Watch the metric data stream for "runtime.jvm.gc.count".

What did you expect to see?
A correct unit can be "{collections}", or "1{collections}", or just "1".

What did you see instead?
The reported unit comes out as "collections".

What version are you using?
1.18

Environment

Additional context
Add any other context about the problem here.

[trask]

thanks for reporting this! it looks like we made this mistake in several places, I can send a PR to fix if you aren't working on it already

[PeterF778]

Please go ahead or assign to me, whatever you prefer.

[trask]

assigning you, thx ❤️

[trask]

Closed by #6930