chore(shellcheck): remove no longer needed disables from config

Author: scop

.shellcheckrc

@@ -4,9 +4,7 @@ enable=require-double-brackets
 disable=SC1090  # not really fixable usually (ever?)
 disable=SC2034  # for localizing variables set in called functions
 disable=SC2128  # intentional style choice
-disable=SC2206  # suggested alternatives fail in posix mode or use temp files
 disable=SC2209  # interferes with our `set` (literal) vs empty booleans
-disable=SC2207  # suggested alternatives fail in posix mode or use temp files
 
 # These disables are to be investigated and decided