Change: Include pre-release changes in release changelog

If the to be released version is not a pre releases include the changes
of the previous pre releases in the changelog.

pontos/release/release.py

@@ -214,7 +214,10 @@ async def run(
             )
             return ReleaseReturnValue.UPDATE_VERSION_ERROR
 
-        last_release_version = get_last_release_version(self.git_tag_prefix)
+        last_release_version = get_last_release_version(
+            self.git_tag_prefix,
+            ignore_pre_releases=not release_version.is_prerelease,
+        )
 
         self.terminal.info(
             f"Creating changelog for {release_version} since "
@@ -252,11 +255,8 @@ async def run(
 
         calculator = command.get_version_calculator()
 
-        next_version = (
-            next_version
-            if next_version is not None
-            else calculator.next_dev_version(release_version)
-        )
+        if not next_version:
+            next_version = calculator.next_dev_version(release_version)
 
         try:
             updated = command.update_version(next_version)

tests/version/test_helper.py

@@ -133,3 +133,16 @@ def test_get_last_release_version_ignore_pre_releases(
         self.assertEqual(
             get_last_release_version(ignore_pre_releases=True), Version("2")
         )
+
+    @patch("pontos.version.helper.Git", spec=Git)
+    def test_get_last_release_version_no_non_pre_release(
+        self, _git_interface_mock
+    ):
+        git_interface = _git_interface_mock.return_value
+        git_interface.list_tags.return_value = [
+            "3.55a1",
+            "3.56.dev1",
+            "4.0.0rc1",
+            "4.0.1b1",
+        ]
+        self.assertIsNone(get_last_release_version(ignore_pre_releases=True))