🎨 Streamline conf.py (#893)

## Description

This PR streamlines `conf.py` by moving two imports to the top of the
file.

## Checklist

- [x] The pull request only contains commits that are focused and
relevant to this change.
- [x] ~~I have added appropriate tests that cover the new/changed
functionality.~~
- [x] ~~I have updated the documentation to reflect these changes.~~
- [x] ~~I have added entries to the changelog for any noteworthy
additions, changes, fixes, or removals.~~
- [x] ~~I have added migration instructions to the upgrade guide (if
needed).~~
- [x] The changes follow the project's style guidelines and introduce no
new warnings.
- [x] The changes are fully tested and pass the CI checks.
- [x] I have reviewed my own code changes.

Author: denialhaag

docs/conf.py

@@ -18,9 +18,13 @@
 from pybtex.style.formatting.unsrt import Style as UnsrtStyle
 from pybtex.style.template import field, href
 
-ROOT = Path(__file__).parent.parent.resolve()
+if TYPE_CHECKING:
+    from pybtex.database import Entry
+    from pybtex.richtext import HRef
 
 
+ROOT = Path(__file__).parent.parent.resolve()
+
 try:
     version = metadata.version("mqt.bench")
 except ModuleNotFoundError:
@@ -29,9 +33,6 @@
 
 # Filter git details from version
 release = version.split("+")[0]
-if TYPE_CHECKING:
-    from pybtex.database import Entry
-    from pybtex.richtext import HRef
 
 project = "MQT Bench"
 author = "Chair for Design Automation, TUM & Munich Quantum Software Company"