Auto merge of #11768 - achals:blob-string, r=Ms2ger

Update Blob::{new, new_inherited} to take Strings

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11762.

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- [X] These changes do not require tests because no logic changes, only interface changes.

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components/script/dom/xmlhttprequest.rs

@@ -1111,7 +1111,7 @@ impl XMLHttpRequest {
 
         // Step 3, 4
         let slice = DataSlice::from_bytes(self.response.borrow().to_vec());
-        let blob = Blob::new(self.global().r(), BlobImpl::new_from_slice(slice), &mime);
+        let blob = Blob::new(self.global().r(), BlobImpl::new_from_slice(slice), mime);
         self.response_blob.set(Some(blob.r()));
         blob
     }