Python: Fix grammar

Co-authored-by: intrigus-lgtm <[email protected]>

Author: RasmusWL

python/tools/recorded-call-graph-metrics/README.md

@@ -4,7 +4,7 @@ also known as _call graph tracing_.
 
 Execute a python program and for each call being made, record the call and callable. This allows us to compare call graph resolution from static analysis with actual data -- that is, can we statically determine the target of each actual call correctly.
 
-This is still in the early stages, and currently only support a very minimal working example (to show that this approach might work).
+This is still in the early stages, and currently only supports a very minimal working example (to show that this approach might work).
 
 The next hurdle is being able to handle multiple calls on the same line, such as