Replace logrus with slog in handlers packages

[norkans7]

contains #658

[codecov]

Codecov Report

Merging #659 (b4ea6ab) into main (1b14a95) will not change coverage.
The diff coverage is 16.66%.

@@           Coverage Diff           @@
##             main     #659   +/-   ##
=======================================
  Coverage   74.04%   74.04%           
=======================================
  Files         100      100           
  Lines       13177    13177           
=======================================
  Hits         9757     9757           
  Misses       2732     2732           
  Partials      688      688           

Files	Coverage Δ
handlers/twiml/handlers.go	80.85% <100.00%> (ø)
handlers/facebook_legacy/handler.go	84.37% <0.00%> (ø)
handlers/hormuud/handler.go	80.73% <0.00%> (ø)
handlers/messagebird/handler.go	73.40% <0.00%> (ø)
handlers/whatsapp_legacy/handler.go	79.26% <0.00%> (ø)

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