build: bump cluster observer to v1.2.0

[takirala]

What problem does this PR solve?:

Bumps to v1.2.0 of cluster-observer

Which issue(s) does this PR fix?:

d2iq.atlassian.net/browse/D2IQ-99463

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

Checklist

• If the PR adds a version bump, ensure there is no breaking change in Licensing model (or NA).
• If a chart is changed or app configuration is significantly changed, the chart version is correctly incremented (so that apps are not automatically upgraded from a previous version of DKP).

[d2iq-mergebot]

This repo has @d2iq-mergebot integration. You can perform the following commands by submitting a comment. Submit a comment with content "@d2iq-mergebot help" to view more detailed help text and examples. Be sure the have a look at the mergebot documentation, too.For help using mergebot, please refer to the README file here: https://github.com/mesosphere/mergebot/blob/main/README.md
Enabled Mergebot commands:
@d2iq-mergebot test all
@d2iq-mergebot test
@d2iq-mergebot override-status
@d2iq-mergebot help
@d2iq-mergebot backport

[coveralls]

Pull Request Test Coverage Report for Build 6579317982

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 79.532%

---

Totals
Change from base Build 6578320822:	0.0%
Covered Lines:	136
Relevant Lines:	171

---

💛 - Coveralls