Wrap headers with AxiosHeaders to prevent incorrect type being passed (…

…#1248)

* Set header type before calling transformer

* Wrap the headers with AxiosHeader object every time

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Co-authored-by: Daniel Cooper <daniel.cooper@sony.com>
Co-authored-by: James Bourne <jamesmbourne@users.noreply.github.com>

src/interceptor.ts

@@ -130,7 +130,8 @@ export const aws4Interceptor = <D = any>({
     }
 
     const { host, pathname, search } = new URL(url);
-    const { data, headers, method } = config;
+    const { data, method } = config;
+    const headers = new AxiosHeaders(config.headers);
 
     const transformRequest = getTransformer(config);