test: improve crypto/random.js coverage

- Call randomBytes with a non-function callback
- Call randomFill with a non-function callback

PR-URL: #17555
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

test/parallel/test-crypto-random.js

@@ -488,6 +488,7 @@ common.expectsError(
 );
 
 [1, true, NaN, null, undefined, {}, []].forEach((i) => {
+  const buf = Buffer.alloc(10);
   common.expectsError(
     () => crypto.randomFillSync(i),
     {
@@ -502,4 +503,22 @@ common.expectsError(
       type: TypeError
     }
   );
+  common.expectsError(
+    () => crypto.randomFill(buf, 0, 10, i),
+    {
+      code: 'ERR_INVALID_CALLBACK',
+      type: TypeError,
+      message: 'Callback must be a function',
+    });
+});
+
+[1, true, NaN, null, {}, []].forEach((i) => {
+  common.expectsError(
+    () => crypto.randomBytes(1, i),
+    {
+      code: 'ERR_INVALID_CALLBACK',
+      type: TypeError,
+      message: 'Callback must be a function',
+    }
+  );
 });