fix(ux): ticket details: show save button only if there is a change

[ssiyad]

• Show save button only if there is a change
• Change background color (darken, bg-gray-900)

[codecov]

Codecov Report

Patch coverage: 35.00% and project coverage change: +0.45 🎉

Comparison is base (75e655f) 12.87% compared to head (db49438) 13.33%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1204      +/-   ##
==========================================
+ Coverage   12.87%   13.33%   +0.45%     
==========================================
  Files          52       52              
  Lines        1848     1852       +4     
==========================================
+ Hits          238      247       +9     
+ Misses       1610     1605       -5     

Impacted Files	Coverage Δ
helpdesk/helpdesk/doctype/hd_ticket/hd_ticket.py	22.92% <15.38%> (+0.40%)	⬆️
helpdesk/utils.py	35.00% <66.66%> (+35.00%)	⬆️
helpdesk/__init__.py	100.00% <100.00%> (ø)

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