fips: otelcol images for linux and windows

[jeffreyc-splunk]

• Requires fips: otelcol binaries for linux and windows #5378
• Images only include the fips-enabled collector and config files (no smart agent bundle, jmx gatherer, etc)
• The config files are just copied from https://github.com/signalfx/splunk-otel-collector/tree/main/cmd/otelcol/config/collector, but without the smartagent components
• TODO: Update gitlab pipeline to build, sign, and release the images/manifests. Need to decide where to push:
  • New repo, e.g. quay.io/signalfx/splunk-otel-collector-fips:<version>. The latest tag would be available.
  • Existing repo with new tags, e.g. quay.io/signalfx/splunk-otel-collector:<version>-fips. The latest tag would be unavailable since they are reserved for the non-fips manifests.

[hughesjj]

Nothing blocking merge but there's some code smells imo

[hughesjj]

nit: Maybe we should bring down the instantiation for the non-fips setting of these variables to live in the "true" conditional block?

[hughesjj]

not for this PR, but does this mean if we set SKIP_BUNDLE="true", the build will fail due to this line? (given FIPS!="true")

It's hard to know if the nested IF statements are intentionally nooping the uncovered else case or if it's just because we didn't want to if [STATEMENT_A] && [STATEMENT_B] the conditional in the parent if block... I'm starting to think it's the latter?

[atoulme]

Thanks for review James. There is more to do but if this passes muster, I'm happy to merge it and we can work on this more. There are still TODOs listed in the PR description that will require us to review further.