Feature: samples testing (#832)

* Check for devxApiUrl override, fetch org and branchName params from the query string and append them to devxapi object

* Change response type to object

* Create an initialState object and pass it to state

* Add check for devxapi params and append them to samplesUrl

* Check for devxapi params and append them to the permissionsUrl

* Create an IDevxAPI interface

* Import IDevxAPI from types and reference it

* Import and reference IAction from the types folder

* Rename the devx-api types file

* Use ternary operator to simplify conditional statement

* Revert "Merge pull request #829 from microsoftgraph/feature/samples-testing"

This reverts commit 220bacb.