PLT-541: make redis client singleton

[n5nk]

Change description

Problem:

• Default pool was having huge connection pool size.
• Redisclient was not singleton in Janusgraph

Analysis:

• The idle connections were huge, as default values were 64 per connection.
• 3 nodes X 64 X 2 pods X 2 connections (metastore and JG) = ~800 were out there. Plus missing of a singleton class for the client was doubling the connection if Redis is restarted, since new connections were established.

Changes:

• Janusgraph:
  - Made redis client creation to be singleton, and also controlled the connection pool size.
  - PR: atlanhq/atlan-janusgraph@9d45e3e
• Per connection and Per node:
  • Max connection pool configured: 20
  • Idle connections: 10

Graph after changes deployed in beta

Type of change

• Bug fix (fixes an issue)
• New feature (adds functionality)

Related issues

Fix #1

Checklists

Development

• Lint rules pass locally
• Application changes have been tested thoroughly
• Automated tests covering modified code pass

Security

• Security impact of change has been considered
• Code follows company security practices and guidelines

Code review

• Pull request has a descriptive title and context useful to a reviewer. Screenshots or screencasts are attached as necessary
• "Ready for review" label attached and reviewers assigned
• Changes have been reviewed by at least one other contributor
• Pull request linked to task tracker where applicable

[checkaayush]

LGTM