[FIX] base_import: prevent trackback while upload unidentified image URL

This issue occurs when a customer imports or uploads a file, and that file
 contains an image that is attached to the URL as text or HTML. then,
 The error would be generated.

  Step to Produce:-
 - import CSV file (Ex.'product.product' model)
    > that CSV file must have one URL Image(In that URL has content of text or
      Html form)
 - Click On the 'Test' Button.

  Applying these changes will resolve this issue.

  sentry:-4046190590

closes odoo/odoo#137611

X-original-commit: acbb5af7ee96cdc579850427bc2bca6d7bf184e4
Signed-off-by: Achraf Ben Azzouz (abz) <abz@odoo.com>

addons/base_import/models/base_import.py

@@ -1263,14 +1263,13 @@ class Import(models.TransientModel):
 
             return base64.b64encode(content)
         except Exception as e:
-            _logger.exception(e)
-            raise ImportValidationError(
-                _(
-                    "Could not retrieve URL: %(url)s [%(field_name)s: L%(line_number)d]: %(error)s",
-                    url=url, field_name=field, line_number=line_number + 1, error=e
-                ),
-                field=field
-            )
+            _logger.warning(e, exc_info=True)
+            raise ValueError(_("Could not retrieve URL: %(url)s [%(field_name)s: L%(line_number)d]: %(error)s") % {
+                'url': url,
+                'field_name': field,
+                'line_number': line_number + 1,
+                'error': e
+            })
 
     def execute_import(self, fields, columns, options, dryrun=False):
         """ Actual execution of the import