[CI:DOCS] update httpd location in tutorial

Update the reference to the httpd in the Podman tutorial.
This just bumps it to F29 for now to get things working,
I'd prefer to get something set up in quay.io to make it
more resistant to Fedora version changes.

Fixes: #6439

Signed-off-by: TomSweeneyRedHat <tsweeney@redhat.com>

docs/tutorials/podman_tutorial.md

@@ -24,7 +24,7 @@ page.
 podman run -dt -p 8080:8080/tcp -e HTTPD_VAR_RUN=/var/run/httpd -e HTTPD_MAIN_CONF_D_PATH=/etc/httpd/conf.d \
                   -e HTTPD_MAIN_CONF_PATH=/etc/httpd/conf \
                   -e HTTPD_CONTAINER_SCRIPTS_PATH=/usr/share/container-scripts/httpd/ \
-                  registry.fedoraproject.org/f27/httpd /usr/bin/run-httpd
+                  registry.fedoraproject.org/f29/httpd /usr/bin/run-httpd
 ```
 Because the container is being run in detached mode, represented by the *-d* in the `podman run` command, Podman
 will print the container ID after it has run. Note that we use port forwarding to be able to