Update install-redhat.yml

modify "add epel repo" to work with RHEL/CentOS 7 & 8

tasks/install-redhat.yml

@@ -30,11 +30,9 @@
     reboot:
 
 - name: add epel repo
-  yum_repository:
-    name: epel
-    description: EPEL YUM repo
-    baseurl: "{{ nvidia_driver_rhel_epel_repo_baseurl }}"
-    gpgkey: "{{ nvidia_driver_rhel_epel_repo_gpgkey }}"
+  yum:
+    - name: "epel-release"
+  state: latest
   environment: "{{proxy_env if proxy_env is defined else {}}}"
 
 - name: install dependencies