benchmarks: create top-level benchmarks folder

Benchmarks aren't tests; create a top-level `benchmarks` folder and move
`tests/benchmarks` to `benchmarks/cli`.

.github/workflows/benchmark.yml

@@ -115,7 +115,7 @@ jobs:
         fi
 
         mkdir benchmark && cd benchmark
-        ../source/tests/benchmarks/benchmark.sh \
+        ../source/benchmarks/cli/benchmark.sh \
             ${SUITE_FLAG} ${DEBUG_FLAG} \
             --admin \
             --baseline-cli "git" --cli "${GIT2_CLI}" --name libgit2 \

benchmarks/cli/benchmark_helpers.sh

@@ -105,7 +105,7 @@ fullpath() {
 }
 
 resources_dir() {
-	cd "$(dirname "$0")/../resources" && pwd
+	cd "$(dirname "$0")/../../tests/resources" && pwd
 }
 
 temp_dir() {