🧰⬆️ Bump CI deps and tame YAML lint tantrums

Fresh PLANTUML, pinned SCP action, and a shiny pre-commit lineup because “latest” is a lifestyle, not a strategy.

.pre-commit-config.yaml

@@ -1,7 +1,7 @@
 ---
 repos:
     - repo: https://github.com/pre-commit/pre-commit-hooks
-      rev: v4.6.0
+      rev: v6.0.0
       hooks:
           - id: trailing-whitespace
           - id: end-of-file-fixer
@@ -9,15 +9,19 @@ repos:
             args: ['--unsafe']
           - id: check-added-large-files
     - repo: https://github.com/python-jsonschema/check-jsonschema
-      rev: 0.29.0
+      rev: 0.35.0
       hooks:
           - id: check-github-actions
             args: [--verbose]
     - repo: https://github.com/rhysd/actionlint
-      rev: v1.7.1
+      rev: v1.7.9
       hooks:
           - id: actionlint
     - repo: https://github.com/jorisroovers/gitlint
       rev: v0.19.1
       hooks:
           - id: gitlint
+    - repo: https://gitlab.com/vojko.pribudic.foss/pre-commit-update
+      rev: v0.9.0
+      hooks:
+        - id: pre-commit-update