Update transaction list to differentiate GraphQL requests

[ArjanSM]

📷 Screenshots

📄 Context

Issue #116 talks about the shortcoming of the initial approach of supporting GraphQL on Chucker.

This PR is an attempt support GraphQL on Chucker using the guidelines mentioned in Issue #116.

📝 Changes

1. Enable clients to set a graphQLEndpoint through the ChuckerInterceptor.Builder
2. Pass the graphQLEndpoint as an argument to the RequestProcessor.process(..) method
3. Add isGraphQLRequest property in the HttpTransaction entity & HttpTransactionTuple
4. Expose isGraphQLRequest via HttpTransactionTuple
5. Tests
6. Update Sample app to illustrate the effects of the change.

📎 Related PR

PR#805 is also doing the same thing but does not handle GraphQL requests via HTTP GET methods. But this PR does not block any other PR.

🚫 Breaking

1. ChuckerInterceptor now contains an additional parameter to represent a GraphQL path or url
2. RequestProcessor's process(..) method would accept the Graphql path passed by Interceptor.

🛠️ How to test

Test cases for RequestProcessor included in the PR.

⏱️ Next steps

[ArjanSM]

@cortinico, @vbuberen My apologies I'm sure you all are very busy and I don't want to pester. I can understand this PR may not be a priority considering you all are in the middle of revamping the HttpTransactionModel.
But could we have a discussion about what the new transaction model would look like and what we could do to support GQL on chucker?

[cortinico]

I'm leaning towards closing this as we're about to merge #805
Can I ask you to rebase your work on top of it?

[ArjanSM]

@cortinico Sure!
I'll close this PR and have a new PR ready instead.