Registering a Pool: remove GitHub & TinyURL (#1100)

* Update register-stake-pool.md

I removed Git as the recommended place for saving metadata and also removed any mention of tinyurl.

* Update docs/operate-a-stake-pool/register-stake-pool.md

Co-authored-by: RdLrT <3169068+rdlrt@users.noreply.github.com>

---------

Co-authored-by: RdLrT <3169068+rdlrt@users.noreply.github.com>
Co-authored-by: Robert Phair <rphair@cosd.com>

docs/operate-a-stake-pool/register-stake-pool.md

@@ -62,7 +62,7 @@ cardano-cli stake-pool metadata-hash --pool-metadata-file poolMetaData.json > po
 
 ## Get the hash of your JSON file
 
-Upload your `poolMetaData.json` file to a web site that you administer or a public web site. For example, you can upload to GitHub.
+Make your poolMetadata.json available as a web URL accessible on internet, ideally without  redirections. You can do so by uploading it to your website as well.
 Verify the metadata hashes by comparing your uploaded .json file and your local .json file's hash.
 
 ```
@@ -149,10 +149,6 @@ In case an error similar to the one below appears, then the URL length needs to
 
 and you must generate the certificate again with the new, shorter URL.
 
-:::tip
-[TinyUrl](https://tinyurl.com/) can used to achieve a shorter URL address.
-:::
-
 ## Create a delegation certificate pledge
 
 To honor your pledge, create a delegation certificate: