docs: migrate to new hooks

Author: raj-sapalya

src/content/contribute/writing-a-plugin.mdx

@@ -31,20 +31,24 @@ A plugin for webpack consists of:
 class MyExampleWebpackPlugin {
   // Define `apply` as its prototype method which is supplied with compiler as its argument
   apply(compiler) {
-    // Specify the event hook to attach to
-    compiler.hooks.emit.tapAsync(
+    // Hook into the compilation
+    compiler.hooks.thisCompilation.tap(
       "MyExampleWebpackPlugin",
-      (compilation, callback) => {
-        console.log("This is an example plugin!");
-        console.log(
-          "Here’s the `compilation` object which represents a single build of assets:",
-          compilation,
+      (compilation) => {
+        // Specify the asset processing hook
+        compilation.hooks.processAssets.tap(
+          {
+            name: "MyExampleWebpackPlugin",
+            stage: compiler.webpack.Compilation.PROCESS_ASSETS_STAGE_ADDITIONS,
+          },
+          (assets) => {
+            console.log("This is an example plugin!");
+            console.log(
+              "Here’s the `compilation` object which represents a single build of assets:",
+              compilation,
+            );
+          },
         );
-
-        // Manipulate the build using the plugin API provided by webpack
-        compilation.addModule(/* ... */);
-
-        callback();
       },
     );
   }