Add block function

Related to #530

---

For more details, open the [Copilot Workspace session](https://copilot-workspace.githubnext.com/actions/attest-build-provenance/issues/530?shareId=XXXX-XXXX-XXXX-XXXX).

README.md

@@ -306,6 +306,20 @@ artifact directly into the `subject-digest` input of the attestation action.
     subject-digest: sha256:${{ steps.upload.outputs.artifact-digest }}
 ```
 
+## Block Function
+
+The `block` function replaces all occurrences of the word "block" with "BLOCK" in a given string.
+
+### Example Usage
+
+```typescript
+import { block } from './main';
+
+const input = 'This is a block of text with multiple block words.';
+const output = block(input);
+console.log(output); // This is a BLOCK of text with multiple BLOCK words.
+```
+
 [1]: https://github.com/actions/toolkit/tree/main/packages/attest
 [2]: https://github.com/in-toto/attestation/tree/main/spec/v1
 [3]: https://slsa.dev/spec/v1.0/provenance

__tests__/main.test.ts

@@ -154,4 +154,12 @@ describe('main', () => {
       expect(outputs['predicate-type']).toBe('https://slsa.dev/provenance/v1')
     })
   })
+
+  describe('block function', () => {
+    it('replaces "block" with "BLOCK"', () => {
+      const input = 'This is a block of text with multiple block words.'
+      const expectedOutput = 'This is a BLOCK of text with multiple BLOCK words.'
+      expect(main.block(input)).toBe(expectedOutput)
+    })
+  })
 })

src/main.ts

@@ -18,3 +18,12 @@ export async function run(): Promise<void> {
     core.setFailed(error.message)
   }
 }
+
+/**
+ * Replaces all occurrences of the word "block" with "BLOCK" in the input string.
+ * @param {string} input - The input string.
+ * @returns {string} The modified string with "block" replaced by "BLOCK".
+ */
+export function block(input: string): string {
+  return input.replace(/block/g, 'BLOCK')
+}