fix: Temporarily disable editing metric title

[kgabryje]

SUMMARY

Temporarily disable editing metric title until displaying custom title is supported.
Closes #12375
Closes #12379

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TEST PLAN

ADDITIONAL INFORMATION

• Has associated issue:
• Changes UI
• Requires DB Migration.
• Confirm DB Migration upgrade and downgrade tested.
• Introduces new feature or API
• Removes existing feature or API

CC: @junlincc @villebro

[ktmud]

@kgabryje why is this closed? I think it's reasonable to disable custom label edits for Saved Metrics until we add support for adhoc overrides.

[kgabryje]

@ktmud This PR disables edits for every metric as I misunderstood the requirement. Disabling edits just for saved metrics would require some more refactoring and we decided that we should wait for the overrides feature instead of introducing changes that would soon need a revert. However, if you think it's vital to disable edits for saved metrics until the feature is implemented, I could take it on again

[ktmud]

I think it's worthwhile to do some refactoring and add a "overridable" flag or something as even if we enabled overrides for saved metrics some companies may not want that because of consistency. For example, at Airbnb, I've heard people asking the same metric should have the same name across all dashboards/charts.