chore(repo): cache documentation script (#27100)

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## Current Behavior
`documentation` is not cacheable. It is reran everytime someone tries to
push, including the following flow:

- git push, fails as docs changes found
- git commit -am "chore(repo): add docs"
- git push, runs full docs cycle again in pre-push hook

## Expected Behavior
`documentation` is cacheable, and avoids rerunning when no fs changes
are made

## Related Issue(s)
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merged. -->

Fixes #

(cherry picked from commit 8f5d3dc)

package.json

@@ -376,7 +376,26 @@
       "check-lock-files",
       "check-codeowners",
       "documentation"
-    ]
+    ],
+    "targets": {
+      "documentation": {
+        "cache": true,
+        "inputs": [
+          "{workspaceRoot}/packages/**", 
+          "{workspaceRoot}/docs/**",
+          "{workspaceRoot}/scripts/documentation/**",
+          "!{workspaceRoot}/docs/generated", 
+          "!{workspaceRoot}/packages/**/*.spec.ts",
+          "!{workspaceRoot}/packages/**/project.json",
+          "!{workspaceRoot}/packages/**/tsconfig.json",
+          "!{workspaceRoot}/packages/**/tsconfig.lib.json",
+          "!{workspaceRoot}/packages/**/tsconfig.spec.json",
+          "!{workspaceRoot}/packages/**/jest.config.{ts,js}",
+          "!{workspaceRoot}/packages/**/.eslintrc.json"
+        ]
+      },
+      "outputs": ["{workspaceRoot}/docs/generated"]
+    }
   },
   "packageManager": "[email protected]"
 }