Shorten introspection to introspect

For conversion functions, we use the name `convert`.
So let's be consistent with introspection functions.
It's also more concise.

Author: ctrueden

src/scyjava/__init__.py

@@ -91,7 +91,7 @@
     to_java,
     to_python,
 )
-from ._introspection import (
+from ._introspect import (
     attrs,
     fields,
     find_java,