docs: specify git protocol is not supported for github hosted repo
Build from URL does not supports `git://` is source is hosted on Github.
Reason:
[CI:DOCS]
[NO NEW TESTS NEEDED]
[NO TESTS NEEDED]
Similar to:
@@ -988,9 +988,11 @@ use it as the context. The Containerfile at the root of the repository will be
used and it only works if the GitHub repository is a dedicated repository.
```
-$ podman build git://github.com/scollier/purpletest
+$ podman build https://github.com/scollier/purpletest
```
+ Note: Github does not support using `git://` for performing `clone` operation due to recent changes in their security guidance (https://github.blog/2021-09-01-improving-git-protocol-security-github/). Use an `https://` URL if the source repository is hosted on Github.
+
#### Building an image using a URL to an archive
Podman will fetch the archive file, decompress it, and use its contents as the
