Merge branch 'docs-aqualls-substitution-suggestions' into 'master'

Docs: try out suggestion-level substitutions

See merge request gitlab-org/gitlab!28060

doc/.vale/gitlab/AfterOnce.yml

+---
+# Suggestion: gitlab.AfterOnce
+#
+# 'Once' is frequently misused at GitLab when the user means 'after'.
+#
+# For a list of all options, see https://errata-ai.github.io/vale/styles/
+extends: substitution
+message: 'Usage check: Use "once" for counting ("Run a job once...") and "after" for a sequence ("Run this job after...").'
+link: https://docs.gitlab.com/ee/development/documentation/styleguide.html#language
+level: suggestion
+ignorecase: true
+swap:
+  once: after

doc/.vale/gitlab/SubstitutionSuggestions.yml

+---
+# Suggestion: gitlab.SubstitutionSuggestions
+#
+# Suggests better options for frequently misused terms at GitLab that are
+# often - but not always - incorrect.
+#
+# For a list of all options, see https://errata-ai.github.io/vale/styles/
+extends: substitution
+message: 'Consider "%s" instead of "%s".'
+link: https://docs.gitlab.com/ee/development/documentation/styleguide.html#language
+level: suggestion
+ignorecase: true
+swap:
+  since: because
+  utilize: use