Update readme to remove drone svg (#27624)

Author: lng2020

README.md

@@ -6,8 +6,8 @@
 <h1 align="center">Gitea - Git with a cup of tea</h1>
 
 <p align="center">
-  <a href="https://drone.gitea.io/go-gitea/gitea" title="Build Status">
-    <img src="https://drone.gitea.io/api/badges/go-gitea/gitea/status.svg?ref=refs/heads/main">
+  <a href="https://github.com/go-gitea/gitea/actions/workflows/release-nightly.yml?query=branch%3Amain" title="Release Nightly">
+    <img src="https://github.com/go-gitea/gitea/actions/workflows/release-nightly.yml/badge.svg?branch=main">
   </a>
   <a href="https://discord.gg/Gitea" title="Join the Discord chat at https://discord.gg/Gitea">
     <img src="https://img.shields.io/discord/322538954119184384.svg">

README_ZH.md

@@ -6,8 +6,8 @@
 <h1 align="center">Gitea - Git with a cup of tea</h1>
 
 <p align="center">
-  <a href="https://drone.gitea.io/go-gitea/gitea" title="Build Status">
-    <img src="https://drone.gitea.io/api/badges/go-gitea/gitea/status.svg?ref=refs/heads/main">
+  <a href="https://github.com/go-gitea/gitea/actions/workflows/release-nightly.yml?query=branch%3Amain" title="Release Nightly">
+    <img src="https://github.com/go-gitea/gitea/actions/workflows/release-nightly.yml/badge.svg?branch=main">
   </a>
   <a href="https://discord.gg/Gitea" title="Join the Discord chat at https://discord.gg/Gitea">
     <img src="https://img.shields.io/discord/322538954119184384.svg">