Fix incorrect output on the genspider command
diff --git a/scrapy/commands/genspider.py b/scrapy/commands/genspider.py
index 72248bdede4..5f44daa70d3 100644
--- a/scrapy/commands/genspider.py
+++ b/scrapy/commands/genspider.py
@@ -98,7 +98,7 @@ def _genspider(self, module, name, domain, template_name, template_file):
         print(f"Created spider {name!r} using template {template_name!r} ",
               end=('' if spiders_module else '\n'))
         if spiders_module:
-            print("in module:\n  {spiders_module.__name__}.{module}")
+            print(f"in module:\n  {spiders_module.__name__}.{module}")
 
     def _find_template(self, template):
         template_file = join(self.templates_dir, f'{template}.tmpl')
diff --git a/tests/test_commands.py b/tests/test_commands.py
index 85aee55a56d..d3ac05eac44 100644
--- a/tests/test_commands.py
+++ b/tests/test_commands.py
@@ -389,8 +389,9 @@ def test_arguments(self):
     def test_template(self, tplname='crawl'):
         args = [f'--template={tplname}'] if tplname else []
         spname = 'test_spider'
+        spmodule = f"{self.project_name}.spiders.{spname}"
         p, out, err = self.proc('genspider', spname, 'test.com', *args)
-        self.assertIn(f"Created spider {spname!r} using template {tplname!r} in module", out)
+        self.assertIn(f"Created spider {spname!r} using template {tplname!r} in module:{os.linesep}  {spmodule}", out)
         self.assertTrue(exists(join(self.proj_mod_path, 'spiders', 'test_spider.py')))
         modify_time_before = getmtime(join(self.proj_mod_path, 'spiders', 'test_spider.py'))
         p, out, err = self.proc('genspider', spname, 'test.com', *args)

When running inside a project, the `genspider` command is outputting string placeholders rather than their actual contents.

Example:
```
$  scrapy genspider example example.com
Created spider 'example' using template 'basic' in module:
  {spiders_module.__name__}.{module}
```

This PR fixes it, by adding the missing f-string prefix to the string that represents that message.

