docs: minor typos (#169)

# Description

Fixing minor typos.

- [x] I have read the [contributing
documantation](https://retina.sh/docs/contributing).
- [x] I signed and signed-off the commits (`git commit -S -s ...`)
- [x] I have correctly attributed the author(s) of the code.
- [x] I have tested the changes locally.
- [x] I have followed the project's style guidelines.
- [x] I have updated the documentation, if necessary.
- [ ] I have added tests, if applicable.

Signed-off-by: Peter Jausovec <[email protected]>

docs/installation/prometheus-unmanaged.md

@@ -29,7 +29,7 @@ Or if you already have the chart installed, upgrade how you see fit, providing t
   helm upgrade prometheus -n kube-system -f deploy/prometheus/values.yaml prometheus-community/kube-prometheus-stack
   ```
 
-Node: Grafana and kube-state metrics may schedule on Windows nodes, the current chart doesn't have node affinity for those components. Some manual intervention may be required.
+Note: Grafana and kube-state metrics may schedule on Windows nodes, the current chart doesn't have node affinity for those components. Some manual intervention may be required.
 
 6. Verify that the Retina Pods are being scraped by port-forwarding the Prometheus server:
 

docs/troubleshooting/basic-metrics.md

@@ -37,9 +37,11 @@ you should see log lines like the following:
 2023-04-16T00:10:55.598Z        info    linuxutil       linuxutil/linuxutil.go:100      Updated ethTool metrics
 ```
 
+If you don't see the log lines, then the plugin is not running correctly.
+
 ### Check Retina ConfigMap
 
-If not then the plugin is not running correctly. Please check retina config map and make sure the plugins is enabled.
+Please check `retina-config` ConfigMap and make sure the plugins is enabled.
 
 ```shell
 kubectl get configmap retina-config -n kube-system -oyaml