Fixed some typos, add a spell check ci and others minor fix (#8890)

This PR adds a spell checker CI action that will fail future PRs if they introduce typos and spelling mistakes.
This spell checker is based on blacklist of common spelling mistakes, so it will not catch everything,
but at least it is also unlikely to cause false positives.

Besides that, the PR also fixes many spelling mistakes and types, not all are a result of the spell checker we use.

Here's a summary of other changes:
1. Scanned the entire source code and fixes all sorts of typos and spelling mistakes (including missing or extra spaces).
2. Outdated function / variable / argument names in comments
3. Fix outdated keyspace masks error log when we check `config.notify-keyspace-events` in loadServerConfigFromString.
4. Trim the white space at the end of line in `module.c`. Check: https://github.com/redis/redis/pull/7751
5. Some outdated https link URLs.
6. Fix some outdated comment. Such as:
    - In README: about the rdb, we used to said create a `thread`, change to `process`
    - dbRandomKey function coment (about the dictGetRandomKey, change to dictGetFairRandomKey)
    - notifyKeyspaceEvent fucntion comment (add type arg)
    - Some others minor fix in comment (Most of them are incorrectly quoted by variable names)
7. Modified the error log so that users can easily distinguish between TCP and TLS in `changeBindAddr`

1 files changed, 3 insertions, 3 deletions

diff --git a/CONTRIBUTING b/CONTRIBUTING
index 22b8efe48..56b71834d 100644
--- a/CONTRIBUTING
+++ b/CONTRIBUTING
@@ -18,7 +18,7 @@ all the support in the mailing list.
 
 There is also an active community of Redis users at Stack Overflow:
 
-    http://stackoverflow.com/questions/tagged/redis
+    https://stackoverflow.com/questions/tagged/redis
 
 Issues and pull requests for documentation belong on the redis-doc repo:
 
@@ -38,10 +38,10 @@ Here you'll see if there is consensus about your idea.
 2. If in step 1 you get an acknowledgment from the project leaders, use the
    following procedure to submit a patch:
 
-    a. Fork Redis on github ( http://help.github.com/fork-a-repo/ )
+    a. Fork Redis on github ( https://docs.github.com/en/github/getting-started-with-github/fork-a-repo )
     b. Create a topic branch (git checkout -b my_branch)
     c. Push to your branch (git push origin my_branch)
-    d. Initiate a pull request on github ( https://help.github.com/articles/creating-a-pull-request/ )
+    d. Initiate a pull request on github ( https://docs.github.com/en/github/collaborating-with-issues-and-pull-requests/creating-a-pull-request )
     e. Done :)
 
 3. Keep in mind that we are very overloaded, so issues and PRs sometimes wait