Fix python-memcached package name
I think that the package name should be used instead of the library (or referenced alongside) for clarity.
@@ -360,7 +360,7 @@ Collected trace data:
[[automatic-instrumentation-db-python-memcache]]
==== Python Memcache
-Library: `memcache` (`>=1.51`)
+Library: `python-memcached` (`>=1.51`)
Instrumented methods:
