Push docs change to other backend modules

Signed-off-by: Alex Eftimie <alex.eftimie@getyourguide.com>

plugins/events-backend-module-azure/README.md

@@ -31,12 +31,12 @@ Install this module:
 yarn add --cwd packages/backend @backstage/plugin-events-backend-module-azure
 ```
 
-Add the event router to the `EventsBackend`:
+Add the event router to the `EventsBackend` instance in `packages/backend/src/plugins/events.ts`:
 
 ```diff
 +const azureEventRouter = new AzureDevOpsEventRouter();
 
- EventsBackend
+new EventsBackend(env.logger)
 +  .addPublishers(azureEventRouter)
 +  .addSubscribers(azureEventRouter);
 // [...]

plugins/events-backend-module-bitbucket-cloud/README.md

@@ -31,12 +31,12 @@ Install this module:
 yarn add --cwd packages/backend @backstage/plugin-events-backend-module-bitbucket-cloud
 ```
 
-Add the event router to the `EventsBackend`:
+Add the event router to the `EventsBackend` instance in `packages/backend/src/plugins/events.ts`:
 
 ```diff
 +const bitbucketCloudEventRouter = new BitbucketCloudEventRouter();
 
- EventsBackend
+new EventsBackend(env.logger)
 +  .addPublishers(bitbucketCloudEventRouter)
 +  .addSubscribers(bitbucketCloudEventRouter);
 // [...]

plugins/events-backend-module-gerrit/README.md

@@ -30,12 +30,12 @@ Install this module:
 yarn add --cwd packages/backend @backstage/plugin-events-backend-module-gerrit
 ```
 
-Add the event router to the `EventsBackend`:
+Add the event router to the `EventsBackend` instance in `packages/backend/src/plugins/events.ts`:
 
 ```diff
 +const gerritEventRouter = new GerritEventRouter();
 
- EventsBackend
+new EventsBackend(env.logger)
 +  .addPublishers(gerritEventRouter)
 +  .addSubscribers(gerritEventRouter);
 // [...]

plugins/events-backend-module-github/README.md

@@ -36,7 +36,7 @@ Add the event router to the `EventsBackend` instance in `packages/backend/src/pl
 ```diff
 +const githubEventRouter = new GithubEventRouter();
 
- EventsBackend
+new EventsBackend(env.logger)
 +  .addPublishers(githubEventRouter)
 +  .addSubscribers(githubEventRouter);
 // [...]

plugins/events-backend-module-gitlab/README.md

@@ -30,12 +30,12 @@ Install this module:
 yarn add --cwd packages/backend @backstage/plugin-events-backend-module-gitlab
 ```
 
-Add the event router to the `EventsBackend`:
+Add the event router to the `EventsBackend` instance in `packages/backend/src/plugins/events.ts`:
 
 ```diff
 +const gitlabEventRouter = new GitlabEventRouter();
 
- EventsBackend
+new EventsBackend(env.logger)
 +  .addPublishers(gitlabEventRouter)
 +  .addSubscribers(gitlabEventRouter);
 // [...]