AMBARI-26536: Support hadoop credential provider for AMS

[develop-vijay]

What changes were proposed in this pull request?

Support hadoop credential provider for AMS

How was this patch tested?

Test 1:

1. Created a new credential store with keystore password
2. Configured hadoop.security.credential.provider.path in ams-site.xml to point to jceks path. Ex: jceks://file/tmp/test.jceks
3. Started the AMS service to observe the passwords are read from cred store

Test 2:

1. Created a new credential store with keystore password
2. Configured hadoop.security.credential.provider.path in ams-site.xml to point to jceks path. Ex: jceks://file/tmp/test.jceks
3. Passwords are present in cred store
4. Started the AMS service to observe the passwords are read from AMS configuration file directly

Test 3:

1. Created a new credential store with keystore password
2. Credential store not configured
3. Started the AMS service to observe the passwords are read from AMS configuration file directly

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