[manager] check the TA CRD before declaring it a dependency

[atoulme]

Description:
The OpenTelemetryCollector has a dependency in some cases on the TA CRD.

If the TA CRD is not present, the OpenTelemetryCollector controller should be able to continue to perform.

[github-actions]

E2E Test Results

 33 files  ±0  221 suites  ±0   3h 39m 50s ⏱️ - 19m 46s
 85 tests ±0   85 ✅ +1  0 💤 ±0  0 ❌  - 1 
225 runs  ±0  225 ✅ +1  0 💤 ±0  0 ❌  - 1 

Results for commit 6ac8cf2. ± Comparison against base commit 9597117.

♻️ This comment has been updated with latest results.

[swiatekm]

If we want to do this, we should also check if the TA CRD is present in the collector webook, and return an error if the user enables target allocator in the collector CR. Then, we could also skip the checks during manifest generation. It should not be the case that if the user enables the embedded target allocator, and the CRD isn't present, the operator just ignores it without any output.