misc: set profile image file selector to suggest image files (#27646)

src/authentic2/forms/widgets.py

@@ -258,3 +258,8 @@ class ProfileImageInput(ClearableFileInput):
         )
     else:
         template_name = "authentic2/profile_image_input.html"
+
+    def __init__(self, *args, **kwargs):
+        attrs = kwargs.pop('attrs', {})
+        attrs['accept'] = 'image/*'
+        super(ProfileImageInput, self).__init__(*args, attrs=attrs, **kwargs)

tests/test_attribute_kinds.py

@@ -442,3 +442,8 @@ def test_profile_image(db, app, admin, mailoutbox, media):
     assert image.width == 200
     assert image.height == 200
     assert john().attributes.cityscape_image.name != profile_filename
+
+    # verify file input mentions image files
+    response = app.get('/accounts/edit/')
+    form = response.form
+    assert form['edit-profile-cityscape_image'].attrs['accept'] == 'image/*'