Update slogan & logo (#2962)

- Update woodpecker slogan to repo too
  we are not just a simple fork anymore 🎉
- use https://github.com/woodpecker-ci/design/blob/main/logo/non-square.svg

server/forge/github/fixtures/hooks.go

@@ -49,7 +49,7 @@ const HookPush = `{
       "site_admin": false
     },
     "html_url": "https://github.com/woodpecker-ci/woodpecker",
-    "description": "Woodpecker is a community fork of the Drone CI system.",
+    "description": "Woodpecker is a simple yet powerful CI/CD engine with great extensibility.",
     "fork": false,
     "url": "https://github.com/woodpecker-ci/woodpecker",
     "forks_url": "https://api.github.com/repos/woodpecker-ci/woodpecker/forks",
@@ -152,7 +152,7 @@ const HookPush = `{
     "members_url": "https://api.github.com/orgs/woodpecker-ci/members{/member}",
     "public_members_url": "https://api.github.com/orgs/woodpecker-ci/public_members{/member}",
     "avatar_url": "https://avatars.githubusercontent.com/u/84780935?v=4",
-    "description": "Woodpecker is a community fork of the Drone CI system."
+    "description": "Woodpecker is a simple yet powerful CI/CD engine with great extensibility."
   },
   "sender": {
     "login": "6543",