doc: Use dnf instead of yum

The yum command has been replaced by the dnf command in recent releases
of Fedora-based distributions. Use the native command instead of
the alias kept for compatibility.

Also fix a few descriptions for quite old releases.

Change-Id: Ieb9090347a4d1e18ca98c6374cafc7ad66a4b5d7

api-guide/source/dogtag_setup.rst

@@ -35,7 +35,7 @@ To install the required packages:
 
 .. code-block:: bash
 
-    yum install pki-ca pki-kra 389-ds-base
+    dnf install pki-ca pki-kra 389-ds-base
 
 Creating the Directory Server Instance for the Dogtag Internal DB
 *****************************************************************

doc/source/contributor/dependencies.rst

@@ -11,9 +11,9 @@ If you need to add a new dependency to Barbican, you must edit a few things:
 
    .. note:: All dependencies and their version specifiers must come from the
              OpenStack `global requirements`_ repository.
-#. We support deployment on CentOS 6.4, so you should check CentOS + EPEL 6 yum
-   repos to figure out the name of the rpm package that provides the package
-   you're adding. Add this package name as a dependency in
+#. We support deployment on CentOS Stream 9, so you should check CentOS Stream
+   + EPEL 9 yum repos to figure out the name of the rpm package that provides
+   the package you're adding. Add this package name as a dependency in
    ``rpmbuild/SPECS/barbican.spec``.
 #. If there is no package available in CentOS or EPEL, or if the latest
    available package's version is lower than the minimum required version we

doc/source/contributor/testing.rst

@@ -75,11 +75,7 @@ you need to make sure you have all necessary packages installed.
 
     sudo apt-get install python3-dev
 
-- On Fedora 21/RHEL7/CensOS7::
-
-    sudo yum install python3-devel
-
-- On Fedora 22 and higher::
+- On Fedora::
 
     sudo dnf install python3-devel
 

doc/source/install/install-rdo.rst

@@ -16,7 +16,7 @@ Install and configure components
 
    .. code-block:: console
 
-      # yum install openstack-barbican-api
+      # dnf install openstack-barbican-api
 
 .. include:: common_configure.rst
 
@@ -39,7 +39,7 @@ Finalize installation
           WSGIApplicationGroup %{GLOBAL}
           WSGIDaemonProcess barbican-api display-name=barbican-api group=barbican processes=2 threads=8 user=barbican
           WSGIProcessGroup barbican-api
-          WSGIScriptAlias / "/usr/lib/python2.7/site-packages/barbican/api/app.wsgi"
+          WSGIScriptAlias / "/usr/lib/python3.9/site-packages/barbican/api/app.wsgi"
           WSGIPassAuthorization On
       </VirtualHost>
 

doc/source/install/verify.rst

@@ -21,7 +21,7 @@ Verify operation of the Key Manager (barbican) service.
 
      .. code-block:: console
 
-        $ yum install python-barbicanclient
+        $ dnf install python-barbicanclient
 
    * For Ubuntu: