[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

benchmarks/asv.conf.json

@@ -70,8 +70,7 @@
         // the package name by 'pip+', and the package will be installed via
         // pip (with all the conda available packages installed first,
         // followed by the pip installed packages).
-        "req": {
-        },
+        "req": {},
         // same for env variables
         "env": {},
     },