feat(graphql): forces http header value to be lowercase (#1237)

While RFC2616 indicates http header field `names` are case insensitive,
it leaves http header field `values` more open to interpretation,
such as using the text

> Applications ought to follow "common form", where one is known or
indicated, when generating HTTP constructs, since there might exist
some implementations that fail to accept anything beyond the common forms.

This is a small user experience improvement for REST Client users
to prevent a negative experience by using a case sensitive value.

fixes #1236

src/utils/httpRequestParser.ts

@@ -82,7 +82,7 @@ export class HttpRequestParser implements RequestParser {
         removeHeader(headers, 'content-length');
 
         // check request type
-        const isGraphQlRequest = getHeader(headers, 'X-Request-Type') === 'GraphQL';
+        const isGraphQlRequest = getHeader(headers, 'X-Request-Type') === 'GraphQL'.toLowerCase();
         if (isGraphQlRequest) {
             removeHeader(headers, 'X-Request-Type');