add pre-commit hook to facilitate local testing (#9158)

* add pre-commit hook configuration

* add tmp.md to .gitignore

* describe the use of pre-commit hook in CONTRIBUTING.md

* fix docs/integration.md errors identified by markdownlint

* fix docs/<file>.md errors identified by markdownlint

* docs/azure-csi.md
* docs/azure.md
* docs/bootstrap-os.md
* docs/calico.md
* docs/debian.md
* docs/fcos.md
* docs/vagrant.md
* docs/gcp-lb.md
* docs/kubernetes-apps/registry.md
* docs/setting-up-your-first-cluster.md
* docs/vagrant.md
* docs/vars.md

* fix contrib/<file>.md errors identified by markdownlint

docs/calico.md

@@ -124,8 +124,7 @@ You need to edit your inventory and add:
 * `calico_rr` group with nodes in it. `calico_rr` can be combined with
   `kube_node` and/or `kube_control_plane`. `calico_rr` group also must be a child
    group of `k8s_cluster` group.
-* `cluster_id` by route reflector node/group (see details
-[here](https://hub.docker.com/r/calico/routereflector/))
+* `cluster_id` by route reflector node/group (see details [here](https://hub.docker.com/r/calico/routereflector/))
 
 Here's an example of Kubespray inventory with standalone route reflectors: