[release-11.5.3] Alerting docs: clarify `No data/Error` alerts skip pending period (#101867)

Alerting docs: clarify `No data/Error` alerts skip pending period (#101431)

* Alerting docs: clarify `No data/Error` alerts skip pending period

* fix vale errors

(cherry picked from commit a800f87064)

Co-authored-by: Pepe Cano <825430+ppcano@users.noreply.github.com>

docs/sources/alerting/fundamentals/alert-rule-evaluation/state-and-health.md

@@ -68,7 +68,7 @@ Alert instances will be routed for [notifications](ref:notifications) when they
 
 ### `No Data` and `Error` alerts
 
-When evaluation of an alert rule produces state `No Data` or `Error`, Grafana Alerting generates a new alert instance that have the following additional labels:
+When an alert rule evaluation results in a `No Data` or `Error` state, Grafana Alerting immediately creates a new alert instance —skipping the pending period—with the following additional labels:
 
 - `alertname`: Either `DatasourceNoData` or `DatasourceError` depending on the state.
 - `datasource_uid`: The UID of the data source that caused the state.

docs/sources/shared/alerts/table-configure-no-data-and-error.md

@@ -6,9 +6,9 @@ title: 'Table configure no data and error'
 ---
 
 | Configure        | Set alert state | Description                                                                                                                                                                                                                                                   |
-| ---------------- | --------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
-| No Data          | No Data         | The default option for **No Data** events.<br/>Sets alert instance state to `No Data`. <br/> The alert rule also creates a new alert instance `DatasourceNoData` with the name and UID of the alert rule, and UID of the datasource that returned no data as labels. |
-| Error            | Error           | The default option for **Error** events.<br/>Sets alert instance state to `Error`. <br/> The alert rule also creates a new alert instance `DatasourceError` with the name and UID of the alert rule, and UID of the datasource that returned no data as labels.      |
+| ---------------- | --------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
+| No Data          | No Data         | The default option for **No Data** events.<br/>Sets alert instance state to `No Data`. <br/> The alert rule immediately creates a new `DatasourceNoData` alert instance after evaluation, with the alert rule's name, UID, and the data source UID as labels. |
+| Error            | Error           | The default option for **Error** events.<br/>Sets alert instance state to `Error`. <br/> The alert rule immediately creates a new `DatasourceError` alert instance after evaluation, with the alert rule's name, UID, and the data source UID as labels.      |
 | No Data or Error | Alerting        | Sets the alert instance state to `Pending` and then transitions to `Alerting` once the pending period ends. If you sent the pending period to 0, the alert instance state is immediately set to `Alerting`.                                                   |
 | No Data or Error | Normal          | Sets alert instance state to `Normal`.                                                                                                                                                                                                                        |
 | No Data or Error | Keep Last State | Maintains the alert instance in its last state. Useful for mitigating temporary issues.                                                                                                                                                                       |