[dandydev/redis-ha] Add TERM signal trap to Redis-ha fix-split-brain.sh to prevent infinite loop and gracefully exit

[seyyedmojtabarezvani]

What this PR does / why we need it:

When

• A restart occurs for a redis pod
• Some modification (like resource increase) occurs
• draining a node

The command fix-split-brain.sh container will not gracefully exit and goes into an infinite loop and will not be stopped until terminationGracePeriodSeconds timeouts. In this commit a TERM signal trap is added to prevent such a infinite loop and gracefully exit fix-split-brain.sh

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• [x] DCO signed
• [x] Chart Version bumped
• [x] Title of the PR starts with chart name (e.g. [stable/mychartname])