Remove the start and stop logs of the listener

[BuddhiWathsala]

Purpose

Related to ballerina-platform/ballerina-library#2040
Support it only in debug mode.

Examples

Checklist

• Linked to an issue
• Updated the changelog
• Added tests

[codecov]

Codecov Report

Merging #539 (34c0b4c) into master (5fbf543) will increase coverage by 0.02%.
The diff coverage is 33.33%.

@@             Coverage Diff              @@
##             master     #539      +/-   ##
============================================
+ Coverage     81.24%   81.27%   +0.02%     
  Complexity       24       24              
============================================
  Files           127      126       -1     
  Lines          7374     7363      -11     
  Branches       1336     1335       -1     
============================================
- Hits           5991     5984       -7     
+ Misses          925      919       -6     
- Partials        458      460       +2     

Impacted Files	Coverage Δ
...tdlib/grpc/ServerConnectorPortBindingListener.java	33.33% <0.00%> (-38.10%)	⬇️
...b/grpc/callback/StreamingCallableUnitCallBack.java	83.13% <50.00%> (ø)
...tdlib/grpc/callback/UnaryCallableUnitCallBack.java	80.68% <50.00%> (ø)
...lerina/stdlib/grpc/listener/ServerCallHandler.java	79.31% <50.00%> (ø)
...dlib/grpc/listener/StreamingServerCallHandler.java	85.71% <50.00%> (ø)
...stdlib/grpc/ObservableClientConnectorListener.java	85.00% <0.00%> (-5.00%)	⬇️
../ballerina/
... and 1 more

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