KNOX-3310: Fix redundant ALIAS_PASSPHRASE assignment and improve logging

[smolnar82]

KNOX-3310 - Fixing ALIAS_PASSPHRASE issues while importing custom certs.

What changes were proposed in this pull request?

This PR fixes a bug in the Docker entrypoint script and improves logging during the security initialization phase.

Changes

• Bug Fix: Removed the redundant ALIAS_PASSPHRASE assignment within importMultipleCerts. This prevents the script from exiting prematurely (due to set -e) when a keystore password file is not provided.
• Logging Improvements:
  • Added explicit logging to show which file is being used to set the ALIAS_PASSPHRASE.
  • Added logging to indicate when the script falls back to using the MASTER_SECRET.
• Documentation: Added a comment to the importMultipleCerts function to clarify its dependency on the pre-initialized ALIAS_PASSPHRASE variable.

Impact

• Stability: Prevents startup failures in default configurations where KEYSTORE_PASSWORD_FILE is not used.
• Observability: Makes it much easier to debug keystore/truststore password issues by looking at the container logs.

How was this patch tested?

Still needed to be tested in k8s clusters.

Integration Tests

N/A

UI changes

N/A

[github-actions]

Test Results

21 tests   21 ✅  1s ⏱️
 1 suites   0 💤
 1 files     0 ❌

Results for commit 6ed928c.

[moresandeep]

Looks good.