New Module: gio_mime (#7271)

* gio_mime: new module

* multiple changes

- fixed gio_mime module utils handler detection
- add message to test helper assertion
- add unit test

* gio mime output uses unicode smart quotes

* test helper: do not use skip/xfail reason messages - break in old pytest

* Update plugins/modules/gio_mime.py

Co-authored-by: Felix Fontein <felix@fontein.de>

* change exist variables to meet standards

---------

Co-authored-by: Felix Fontein <felix@fontein.de>

tests/unit/plugins/modules/test_gio_mime.yaml

@@ -0,0 +1,70 @@
+# -*- coding: utf-8 -*-
+# Copyright (c) Alexei Znamensky (russoz@gmail.com)
+# GNU General Public License v3.0+ (see LICENSES/GPL-3.0-or-later.txt or https://www.gnu.org/licenses/gpl-3.0.txt)
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+---
+- id: test_set_handler
+  input:
+    handler: google-chrome.desktop
+    mime_type: x-scheme-handler/http
+  output:
+    handler: google-chrome.desktop
+    changed: true
+  run_command_calls:
+    - command: [/testbin/gio, mime, x-scheme-handler/http]
+      environ: &env-def {environ_update: {LANGUAGE: C, LC_ALL: C}, check_rc: true}
+      rc: 0
+      out: ""
+      err: >
+        No default applications for “x-scheme-handler/http”
+    - command: [/testbin/gio, mime, x-scheme-handler/http, google-chrome.desktop]
+      environ: *env-def
+      rc: 0
+      out: "Set google-chrome.desktop as the default for x-scheme-handler/http\n"
+      err: ""
+- id: test_set_handler_check
+  input:
+    handler: google-chrome.desktop
+    mime_type: x-scheme-handler/http
+  output:
+    handler: google-chrome.desktop
+    changed: true
+  flags:
+    skip: test helper does not support check mode yet
+  run_command_calls:
+    - command: [/testbin/gio, mime, x-scheme-handler/http]
+      environ: *env-def
+      rc: 0
+      out: ""
+      err: >
+        No default applications for “x-scheme-handler/http”
+    - command: [/testbin/gio, mime, x-scheme-handler/http, google-chrome.desktop]
+      environ: *env-def
+      rc: 0
+      out: "Set google-chrome.desktop as the default for x-scheme-handler/http\n"
+      err: ""
+- id: test_set_handler_idempot
+  input:
+    handler: google-chrome.desktop
+    mime_type: x-scheme-handler/http
+  output:
+    handler: google-chrome.desktop
+    changed: false
+  run_command_calls:
+    - command: [/testbin/gio, mime, x-scheme-handler/http]
+      environ: *env-def
+      rc: 0
+      out: |
+        Default application for “x-scheme-handler/https”: google-chrome.desktop
+        Registered applications:
+          brave-browser.desktop
+          firefox.desktop
+          google-chrome.desktop
+          firefox_firefox.desktop
+        Recommended applications:
+          brave-browser.desktop
+          firefox.desktop
+          google-chrome.desktop
+          firefox_firefox.desktop
+      err: ""