YDBOPS-9691 fix GRPC TLS certificates in dynnodes

[kobzonega]

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Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Error with dynnodes registration withou command line argument --grpc-ca (KIKIMR-16728):

ssl_transport_security.cc:1514] Handshake failed with fatal error SSL_ERROR_SSL: error:1416F086:SSL routines:tls_process_server_certificate:certificate verify failed.

Issue Number: YDBOPS-9691

What is the new behavior?

• Add --grpc-ca, --grpc-cert and --grpc-key command line args to Database pods when GRPC TLS enabled

Other information

• Fixes volumeMount paths and filenames to use const variables