Typo Update trace_rpc_apis.md (hyperledger#7868)

"ope.ex.mem" should be "op.ex.mem" — The abbreviation for "opcode execution" should be "op" rather than "ope."

Corrected.

Signed-off-by: Dmitry <98899785+mdqst@users.noreply.github.com>
Co-authored-by: Sally MacFarlane <macfarla.github@gmail.com>
Signed-off-by: Marlene Marz <m.marz@kabelmail.de>

docs/trace_rpc_apis.md

@@ -16,7 +16,7 @@ implementations of Besu might track gas refunds separately.
 
 ### Returned Memory from Calls
 
-In the `vmTrace` `ope.ex.mem` fields Besu only reports actual data returned
+In the `vmTrace` `op.ex.mem` fields Besu only reports actual data returned
 from a `RETURN` opcode.  Other implementations return the contents of the 
 reserved output space for the call operations.  Note two major differences: