ci: relax commitlint scope-empty rule

Bare top-level types like `ci:` and `docs:` are valid Conventional
Commits subjects per the spec; the scope segment is optional. The
project's commitlint config previously required a scope on every
commit (`scope-empty: [2, never]`), which is stricter than the spec
and rejects perfectly conformant commit subjects. Demoting the rule
to level 0 (disabled) leaves the scope-enum allowlist enforced for
commits that DO declare a scope, while permitting bare-type subjects.

Signed-off-by: MicrosoftWindows96 <spam@zagrosi.com>

Author: zagrosi-code

commitlint.config.mjs

@@ -24,7 +24,7 @@ export default {
       'ci',
       'deps',
     ]],
-    'scope-empty':          [2, 'never'],
+    'scope-empty':          [0, 'never'],
     'subject-case':         [2, 'never', ['pascal-case', 'upper-case']],
     'subject-full-stop':    [2, 'never', '.'],
     'header-max-length':    [2, 'always', 100],