docs: Fix ignition docs (#300)

## Type of change

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## Changes

The following changes have been made:

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- Change 2

## Notes

- Note 1

## Related Issues

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## Checklist

- [ ] I have linked to any relevant issues.
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areas.
- [ ] I have updated the documentation where relevant (API docs, the
reference, and the Sway book).
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Co-authored-by: K1-R1 <[email protected]>
Co-authored-by: Cameron Carstens <[email protected]>

examples/asset/metadata_docs/src/main.sw

@@ -20,14 +20,14 @@ storage {
 }
 // ANCHOR_END: src7_storage
 
-// ANCHOR src7_metadata_convenience_function
+// ANCHOR: src7_metadata_convenience_function
 impl SRC7 for Contract {
     #[storage(read)]
     fn metadata(asset: AssetId, key: String) -> Option<Metadata> {
         _metadata(storage.metadata, asset, key)
     }
 }
-// ANCHOR src7_metadata_convenience_function
+// ANCHOR_END: src7_metadata_convenience_function
 
 // ANCHOR: src7_set_metadata
 impl SetAssetMetadata for Contract {