Remove an unnecessary import from the ansiballz wrapper (#41747)

changelogs/fragments/ansiballz_streamline_imports.yaml

@@ -0,0 +1,3 @@
+---
+minor_changes:
+- Removed an unnecessary import from the AnsiballZ wrapper

lib/ansible/executor/module_common.py

@@ -143,12 +143,6 @@ if sys.version_info < (3,):
 else:
     unicode = str
     PY3 = True
-try:
-    # Python-2.6+
-    from io import BytesIO as IOStream
-except ImportError:
-    # Python < 2.6
-    from StringIO import StringIO as IOStream
 
 ZIPDATA = """%(zipdata)s"""