Add github label sync

Author: termoshtt

.github/labels.yml

@@ -0,0 +1,18 @@
+- name: add
+  description: Add new features.
+  color: "006400"
+- name: change
+  description: Change existing functionality.
+  color: "fbca04"
+- name: deprecate
+  description: Mark as soon-to-be removed features.
+  color: "a9a9a9"
+- name: remove
+  description: Remove features.
+  color: "dda0dd"
+- name: bug
+  description: Fix bug.
+  color: "dc143c"
+- name: security
+  description: In case of vulnerabilities.
+  color: "800080"

.github/workflows/github-label-sync.yml

@@ -0,0 +1,16 @@
+name: github-label-sync
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - .github/workflows/github-label-sync.yml
+      - .github/labels.yml
+  workflow_dispatch:
+
+jobs:
+  sync:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: r7kamura/github-label-sync-action@v0