[rust-server] Added API Key auth to rust-server

Created by: Herrera93

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Description of the PR

Added API Key authentication in rust-server for both in header and query. Still missing in cookie.

For query, since we're not available to modify hyper request after creating it, I added it to the uri created. To do this I had to move let query_string = ... outside of the queryParams block which means it'll be present even if there aren't any queryParams or query API Key. I think we can change this by creating an additional property to check for both conditions.

For header it was easier since we can use header_mut on request to add any new headers to it. I only added the variable x-keyVarName to vendor extensions in order to camel case the header.

One other downside to this is that we may need to refactor it in case of multiple API Keys in headers.