Add CI workflow to synchronize with shared repository labels

On every push that changes relevant files, and periodically, configure the repository's issue and pull request labels
according to the universal, shared, and local label configuration files.

.github/label-configuration-files/labels.yml

@@ -0,0 +1,36 @@
+# Used by the "Sync Labels" workflow
+# See: https://github.com/Financial-Times/github-label-sync#label-config-file
+
+- name: "status: maintenance required"
+  color: "ff0000"
+  description: Infrastructure failure unrelated to request
+- name: "topic: invalid"
+  color: "ff0000"
+  description: Request could not be processed
+- name: "topic: modification"
+  color: "00ffff"
+  description: Change existing list entry
+- name: "topic: other"
+  color: "00ffff"
+  description: Something other than a library list request
+- name: "topic: release removal"
+  color: "00ffff"
+  description: Remove a library release
+- name: "topic: removal"
+  color: "00ffff"
+  description: Remove library from the list
+- name: "topic: rename"
+  color: "00ffff"
+  description: Change registered library name
+- name: "topic: security"
+  color: "ff0000"
+  description: Related to the protection of user data
+  notes: |
+    Vulnerability disclosures are made following the procedure at:
+    https://github.com/arduino/.github/blob/master/SECURITY.md
+- name: "topic: submission"
+  color: "00ffff"
+  description: Add library to the list
+- name: "topic: URL change"
+  color: "00ffff"
+  description: Change library repository URL