improvement: add `.ash` suffix to the event category #4

Job	Run time
ash-ci / mix deps.get	18s
ash-ci / mix hex.audit	23s
ash-ci / MIX_ENV=test mix.compile	2m 16s
ash-ci / MIX_ENV=dev mix.compile	2m 17s
ash-ci / mix dialyzer	6m 12s
ash-ci / mix sobelow	47s
ash-ci / mix credo --strict	8s
ash-ci / mix format --check-formatted	41s
ash-ci / mix spark.formatter --check	8s
ash-ci / mix spark.cheat_sheets --check	35s
ash-ci / mix test	1m 24s
ash-ci / mix deps.unlock --check-unused	48s
ash-ci / Release	0s
	15m 57s

Provide feedback