chore: update chechout to v4

.github/workflows/tests.yaml

@@ -7,7 +7,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Luacheck
         uses: lunarmodules/luacheck@v1

README.md

@@ -1,2 +1,8 @@
 <h1 align="center">extensions</h1>
 <h2 align="center">Extensions for OxygeNvim</h2>
+
+<p align="center">
+  <img alt="Stargazers" src="https://img.shields.io/github/stars/OxygeNvim/packs?style=for-the-badge&colorA=0b1221&colorB=ff8e8e" />
+  <img alt="Last commit" src="https://img.shields.io/github/last-commit/OxygeNvim/packs?style=for-the-badge&colorA=0b1221&colorB=BDB0E4" />
+  <img alt="Issues" src="https://img.shields.io/github/issues/OxygeNvim/packs?style=for-the-badge&colorA=0b1221&colorB=FBC19D" />
+</p>