Add docs for bitbucket commit status

Signed-off-by: Somtochi Onyekwere <[email protected]>
Signed-off-by: Alan Hollis <[email protected]>

docs/spec/v1beta1/provider.md

@@ -274,6 +274,14 @@ spec:
 
 The provider type can be: `github`, `gitlab`, `bitbucket` or `azuredevops`.
 
+For bitbucket, the token should contain the username and [app password](https://support.atlassian.com/bitbucket-cloud/docs/app-passwords/#Create-an-app-password) 
+in the format `<username>:<password>`. The app password should have `Repositories (Read/Write)` permission.
+
+You can create the secret using this command:
+```shell
+kubectl create secret generic api-token --from-literal=token=<username>:<app-password>
+```
+
 #### Authentication
 
 GitHub. GitLab, and Azure DevOps use personal access tokens to authenticate with their API:

docs/spec/v1beta1/receiver.md

@@ -249,6 +249,10 @@ spec:
 Note that you have to set the generated token as the Bitbucket server webhook secret value.
 The controller uses the `X-Hub-Signature` HTTP header to verify that the request is legitimate.
 
+Also note, the *Bitbucket cloud* service does not yet provide any support for signing webhook requests.
+([1](https://jira.atlassian.com/browse/BCLOUD-14683), [2](https://jira.atlassian.com/browse/BCLOUD-12195)).
+If your repositories are on Bitbucket cloud, you will need to use the Generic receiver instead.
+
 ### Harbor receiver
 
 ```yaml