Fix various typos of software names (#18083)

* `git` -> `Git`
* `Github` and `github` -> `GitHub`
* `crowdin` -> `Crowdin`
* `git-lfs` -> `Git LFS`
* `githooks`, `git hooks`, `git-hooks` -> `Git Hooks`
* `discord` -> `Discord`
* `2fa` -> `2FA`
* `gitlab` and `Gitlab` -> `GitLab`
* `web hook` -> `webhook`
* `linux` -> `Linux`
* `sqlite` -> `SQLite`
* `MYSQL` and `mysql` -> `MySQL`
* rename refs to `master` branch -> `main`
* Fix English grammar

docs/content/doc/installation/with-docker-rootless.en-us.md

@@ -19,7 +19,7 @@ Gitea provides automatically updated Docker images within its Docker Hub organiz
 possible to always use the latest stable tag or to use another service that handles updating
 Docker images.
 
-The rootless image use Gitea internal ssh to provide git protocol and doesn't support openssh.
+The rootless image use Gitea internal SSH to provide Git protocol and doesn't support OpenSSH.
 
 This reference setup guides users through the setup based on `docker-compose`, but the installation
 of `docker-compose` is out of scope of this documentation. To install `docker-compose` itself, follow