refs CNVS-27581
this ensures we have one correlation ID for a request coming
through the ecosystem rather than a seperate ID for each request
at each service. Each request id must be signed to make sure
others can't just submit whatever they want.
TEST PLAN:
1) make an API request and provide the header 'X-Request-Context-Id'
2) make sure to include the X-Request-Context-Signature header, which
should have the value of the sha512 signature with the shared
secret for the services ecosystem
2) the logs should show your provided value as the context Id for that
canvas request
Change-Id: I610fbe8c4df355d43c05360670f80971d1459644
Reviewed-on: https://gerrit.instructure.com/73166
Tested-by: Jenkins
Reviewed-by: Simon Williams <simon@instructure.com>
QA-Review: Jeremy Putnam <jeremyp@instructure.com>
Product-Review: Ethan Vizitei <evizitei@instructure.com>