feat(diagnostics): demote heap/thread dumps features to BETA feature level

[andrewazores]

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Related to cryostatio/cryostat#1172
See #1838

Description of the change:

This change adds allows a match expression example to be copied to the clipboard...

Motivation for the change:

This change is helpful because users may want to copy the example for easier use...

How to manually test:

1. Run CRYOSTAT_IMAGE=quay.io... sh smoketest.sh...
2. ...