hacking/test-module: fix for python3 (#26194)

* make hacking/test-module compatible with python3

hacking/test-module

@@ -42,6 +42,7 @@ from ansible.parsing.utils.jsonify import jsonify
 from ansible.parsing.splitter import parse_kv
 import ansible.executor.module_common as module_common
 import ansible.constants as C
+from ansible.module_utils._text import to_text
 
 try:
     import json
@@ -159,7 +160,7 @@ def boilerplate_module(modfile, args, interpreters, check, destfile):
     print("* including generated source, if any, saving to: %s" % modfile2_path)
     if module_style not in ('ansiballz', 'old'):
         print("* this may offset any line numbers in tracebacks/debuggers!")
-    modfile2 = open(modfile2_path, 'w')
+    modfile2 = open(modfile2_path, 'wb')
     modfile2.write(module_data)
     modfile2.close()
     modfile = modfile2_path
@@ -178,6 +179,7 @@ def ansiballz_setup(modfile, modname, interpreters):
 
     cmd = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
     out, err = cmd.communicate()
+    out, err = to_text(out, errors='surrogate_or_strict'), to_text(err)
     lines = out.splitlines()
     if len(lines) != 2 or 'Module expanded into' not in lines[0]:
         print("*" * 35)
@@ -209,6 +211,7 @@ def runtest(modfile, argspath, modname, module_style, interpreters):
 
     cmd = subprocess.Popen(invoke, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
     (out, err) = cmd.communicate()
+    out, err = to_text(out), to_text(err)
 
     try:
         print("*" * 35)