Corrected a typo.

Author: StuntsPT

docs/mkdocs.yml

@@ -7,7 +7,7 @@ pages:
     - 'Usage': 'usage.md'
     - 'Output': 'output.md'
     - 'Test Data': 'test_data.md'
-    - 'Benchmarking': 'benckmark.md'
+    - 'Benchmarking': 'benchmark.md'
     - 'Citation': 'citation.md'
     - 'Future Plans': 'future.md'
     - 'FAQ': 'faq.md'