MPL-2 license is missing from the template

[jni]

When I tried to make a plugin and selected the MPL-2 license, I got the following traceback during plugin creation:

Traceback (most recent call last):
  File "/Users/jni/micromamba/envs/copier/bin/copier", line 10, in <module>
    sys.exit(CopierApp.run())
             ^^^^^^^^^^^^^^^
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/plumbum/cli/application.py", line 638, in run
    inst, retcode = subapp.run(argv, exit=False)
                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/plumbum/cli/application.py", line 633, in run
    retcode = inst.main(*tailargs)
              ^^^^^^^^^^^^^^^^^^^^
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/cli.py", line 281, in main
    return _handle_exceptions(inner)
           ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/cli.py", line 70, in _handle_exceptions
    method()
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/cli.py", line 272, in inner
    with self._worker(
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/main.py", line 228, in __exit__
    raise value
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/cli.py", line 279, in inner
    worker.run_copy()
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/main.py", line 827, in run_copy
    self._render_folder(src_abspath)
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/main.py", line 697, in _render_folder
    self._render_file(file)
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/copier/main.py", line 618, in _render_file
    new_content = tpl.render(**self._render_context()).encode()
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/jinja2/environment.py", line 1304, in render
    self.environment.handle_exception()
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/jinja2/environment.py", line 939, in handle_exception
    raise rewrite_traceback_stack(source=source)
  File "/private/var/folders/z7/mv1jznhx59q5vc3bp09gj69m0000gn/T/copier.vcs.clone.cb7akvc2/template/LICENSE.jinja", line 12, in top-level template code
  File "/Users/jni/micromamba/envs/copier/lib/python3.12/site-packages/jinja2/loaders.py", line 207, in get_source
    raise TemplateNotFound(template)
jinja2.exceptions.TemplateNotFound: template/licenses/MPL-2.jinja

[GenevieveBuckley]

PR to fix this here: #16