Fix SecretGroup common policy path

[john-odonnell]

Desired Outcome

From ONYX-14902:

We added the secrets-policy-path annotation but it does not appear to be working as intended.
Write some unit tests to cover the functionality (mostly here) and make sure the annotation is documented in PUSH_TO_FILE.md.

When the annotation conjur.org/conjur-secrets-policy-path.{secret-group} is set, it defines a common policy path prefix, assumed to be relative to the root policy. Policy paths defined in conjur.org/conjur-secrets.{secret-group} are relative to this common path.

When the annotation is not set, the policy paths defined in conjur.org/conjur-secrets.{secret-group} are themselves relative to the root policy.

Implemented Changes

• The function newSecretGroup constructs a new SecretGroup sg, then makes a call to sg.resolveSecretSpecs().
  • If a common policy path has been provided by with the annotation conjur.org/conjur-secret-policy-path.{secret-group}, then the SecretSpecs field is replaced by a copy of itself, with all secret paths being prepended with the common policy path.
  • If a common policy path has NOT been provided, then existing slice in field SecretSpecs is assumed to contain fully-qualified policy paths to Conjur secrets, and it not updated.
• Updated happy path test cases in secret_group_test.go
• PUSH_TO_FILE.md updated to describe conjur.org/conjur-secret-policy-path.{secret-group} annotation. Included an example to show two functionally identical annotation sets, one with a common policy prefix, and one without.

Connected Issue/Story

CyberArk internal issue link: ONYX-14092

Definition of Done

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merged.

Changelog

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  CHANGELOG update

Test coverage

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• The changes in this PR do not require tests

Documentation

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Behavior

• This PR changes product behavior and has been reviewed by a PO, or
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• No behavior was changed with this PR

Security

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• These changes are part of a larger initiative with a separate security review, or
• There are no security aspects to these changes

[codeclimate]

Code Climate has analyzed commit 586c74a and detected 0 issues on this pull request.

The test coverage on the diff in this pull request is 100.0% (50% is the threshold).

This pull request will bring the total coverage in the repository to 92.8% (1.3% change).

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[diverdane]

LGTM!!!