fix: adds whitespace between bug and in for EOT messages

[adarsh0728]

What this PR does / why we need it

Adds whitespace between bug and in when sending partial responses message to the users

[yhl25]

Can we fix the details page to align with the headings?

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 79.74%. Comparing base (75c6158) to head (ce9844e).

Files with missing lines	Patch %	Lines
rust/numaflow-core/src/sinker/sink/user_defined.rs	0.00%	1 Missing ⚠️
rust/numaflow-core/src/transformer.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3078      +/-   ##
==========================================
+ Coverage   79.72%   79.74%   +0.01%     
==========================================
  Files         291      291              
  Lines       65063    65063              
==========================================
+ Hits        51873    51884      +11     
+ Misses      12638    12629       -9     
+ Partials      552      550       -2     

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[adarsh0728]

Can we fix the details page to align with the headings?

yes will do in this PR