16704 - Define a default help_text for ColorField (#16708)

* Added `help_text` to ColorField.

* Addressed PR comment to remove the redundant help_text from all the forms where ColorField was used.

* Add space before example value

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Co-authored-by: Jeremy Stretch <jstretch@netboxlabs.com>

netbox/extras/forms/bulk_import.py

@@ -228,9 +228,6 @@ class TagImportForm(CSVModelForm):
     class Meta:
         model = Tag
         fields = ('name', 'slug', 'color', 'description')
-        help_texts = {
-            'color': mark_safe(_('RGB color in hexadecimal. Example:') + ' <code>00ff00</code>'),
-        }
 
 
 class JournalEntryImportForm(NetBoxModelImportForm):