Fix validation performance bug - goto-bus-stop in issue/862, pull/863
Adds a cache in fragment spread validation, fixing a situation where validating a query
with many fragment spreads against a schema with many interfaces could take multiple
seconds to validate.
Maintenance
Remove ariadne byte/char mapping - goto-bus-stop in pull/855
Generating JSON or CLI reports for apollo-compiler diagnostics used a translation layer
between byte offsets and character offsets, which cost some computation and memory
proportional to the size of the source text. The latest version of ariadne allows us to
remove this translation.
Fixes
Maintenance