Bump prometheus.prometheus to 0.26.2

And little update information in README.rst

Change-Id: I8ea3cf1ec6a9561483e5552b9308c4a8798065ac

prometheus/README.rst

@@ -1,6 +1,6 @@
+==================
 Install Prometheus
-##################
-:tags: openstack, ansible
+==================
 
 About this repository
 ---------------------
@@ -8,8 +8,6 @@ About this repository
 This set of playbooks will deploy Prometheus. If this is being deployed as part of
 an OpenStack all of the inventory needs will be provided for.
 
-**These playbooks require Ansible 2.4+.**
-
 Deployment Process
 ------------------
 
@@ -18,7 +16,7 @@ Clone the repo
 .. code-block:: bash
 
     cd /opt
-    git clone https://github.com/openstack/openstack-ansible-ops
+    git clone https://opendev.org/openstack/openstack-ansible-ops
 
 Downloading role dependencies
 
@@ -27,7 +25,6 @@ Downloading role dependencies
     cd /opt/openstack-ansible-ops/prometheus
     ansible-galaxy install -r requirements.yml
 
-
 Install node_exporter
 
 .. code-block:: bash
@@ -35,7 +32,6 @@ Install node_exporter
     cd /opt/openstack-ansible-ops/prometheus
     openstack-ansible installNodeExporter.yml
 
-
 If you want to deploy the mysqld_exporter, you need to create the Galera user for it first
 
 .. code-block:: yaml
@@ -50,7 +46,6 @@ If you want to deploy the mysqld_exporter, you need to create the Galera user fo
         check_hostname: false
         state: present
 
-
 Then install the mysqld_exporter
 
 .. code-block:: bash

prometheus/requirements.yml

@@ -2,5 +2,5 @@
 
 collections:
 - name: prometheus.prometheus
-  version: 0.25.0
+  version: 0.26.2
   type: galaxy