teamcity/example-orms: example-orms isn't a pinned revision when running CI

[irfansharif]

#42042, a backport to release-v2.1 was failing on TC due to Example ORM tests. Debugging that I noticed that our TC setup does not use a pinned revision of example-orms when running the test suite (it simply picks up whatever is on master). This means that any and every change pushed out to https://github.com/cockroachdb/examples-orms is what gets used for all future TC runs against all branches (including all the way back to release-v2.1). This is probably not what we want (#42042 (comment)).

Jira issue: CRDB-5389

[irfansharif]

+cc @rohany, @rafiss for triage.

[kenliu]

@apantel I think this is related to the work you are doing with pinning versions

[rafiss]

I don't think we'll prioritize this work. For the past few years, this issue hasn't caused much disruption. The way we workaround it is to teach examples-orms about which CRDB versions various tests are expected to work with. Example: https://github.com/cockroachdb/examples-orms/blob/1e65311aeebffed07371d258bfcf7fbe4abf01c8/testing/main_test.go#L191-L194