backend-plugin-api: switch createBackendPlugin id -> pluginId

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

docs/backend-system/architecture/04-plugins.md

@@ -22,7 +22,7 @@ import {
 } from '@backstage/backend-plugin-api';
 
 export const examplePlugin = createBackendPlugin({
-  id: 'example',
+  pluginId: 'example',
   register(env) {
     env.registerInit({
       deps: {
@@ -53,7 +53,7 @@ export interface ExamplePluginOptions {
 
 export const examplePlugin = createBackendPlugin(
   (options?: ExamplePluginOptions) => ({
-    id: 'example',
+    pluginId: 'example',
     register(env) {
       env.registerInit({
         deps: {

docs/backend-system/architecture/05-extension-points.md

@@ -44,7 +44,7 @@ class ActionsExtension implements ScaffolderActionsExtensionPoint {
 
 export const scaffolderPlugin = createBackendPlugin(
   {
-    id: 'scaffolder',
+    pluginId: 'scaffolder',
     register(env) {
       const actionsExtensions = new ActionsExtension();
       env.registerExtensionPoint(

docs/backend-system/architecture/07-naming-patterns.md

@@ -21,7 +21,7 @@ Example:
 
 ```ts
 export const catalogPlugin = createBackendPlugin({
-  id: 'catalog',
+  pluginId: 'catalog',
   ...
 })
 ```
@@ -36,7 +36,7 @@ export const catalogPlugin = createBackendPlugin({
 Example:
 
 ```ts
-export const catalogModuleGithubEntityProvider = createBackendPlugin({
+export const catalogModuleGithubEntityProvider = createBackendModule({
   pluginId: 'catalog',
   moduleId: 'githubEntityProvider',
   ...