release-25.2: roachtest: don't run nodejs-postgres on FIPS architecture

[rafiss]

Backport 1/1 commits from #156692 on behalf of @rafiss.

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This library does not support FIPS.

fixes #156439
Release note: None

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Release justification:

[blathers-crl]

Thanks for opening a backport.

Before merging, please confirm that it falls into one of the following categories (select one):

• Non-production code changes. Includes test-only changes, build system changes, etc.
• Fixes for serious issues. Defined in the policy as correctness, stability, or security issues, data corruption/loss, significant performance regressions, breaking working and widely used functionality, or an inability to detect and debug production issues.
• Other approved changes. These changes must be gated behind a disabled-by-default feature flag unless there is a strong justification not to.

Add a brief release justification to the PR description explaining your selection.

Also, confirm that the change does not break backward compatibility and complies with all aspects of the backport policy.

All backports must be reviewed by the TL and EM for the owning area.

[blathers-crl]

✅ PR #156783 is compliant with backport policy

Confidence: high
Backward compatible: true
Explanation: The pull request involves changes only to a file recognized as non-production code under the backport policy. The modified file (pkg/cmd/roachtest/tests/nodejs_postgres.go) falls within the pkg/cmd/roachtest/ path, which is explicitly listed as pertaining to development tools in the policy. Thus, this PR is exempt from the critical bug or feature flag requirements typically necessary for backport compliance.

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}

[cockroach-teamcity]

This change is 

[rafiss]

this branch doesn't have the "except FIPS" spec

nogo: nogo: error running analyzers: 44 analyzers skipped due to type-checking error: pkg/cmd/roachtest/tests/nodejs_postgres.go:180:57: undefined: spec.AllExceptFIPS