[7.x] [APM] Display throughput as tps (instead of tpm) when bucket size < 60 seconds (#107850)

[sorenlouv]

Backports the following commits to 7.x:

• [APM] Display throughput as tps (instead of tpm) when bucket size < 60 seconds ([APM] Display throughput as tps (instead of tpm) when bucket size < 60 seconds #107850)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: ff956e5
• Storybooks Preview

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
apm	4.3MB	4.3MB	+2.5KB

Unknown metric groups

Non-exported public API item count

id	before	after	diff
apm	29	30	+1

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@elasticmachine merge upstream