Revert "Fix case of the "Cirq" project name for oss-fuzz"

Change project name back to lowercase as it needs to work
as (lowercase-only) Docker image name.

Refs:

- #7625 (comment)
- ToastCheng/oss-fuzz@7deb0b7

This reverts commit 31f8647.

Author: pavoljuhas

.github/workflows/cifuzz.yml

@@ -11,12 +11,12 @@ jobs:
       id: build
       uses: google/oss-fuzz/infra/cifuzz/actions/build_fuzzers@master
       with:
-        oss-fuzz-project-name: Cirq
+        oss-fuzz-project-name: cirq
         language: python
     - name: Run Fuzzers
       uses: google/oss-fuzz/infra/cifuzz/actions/run_fuzzers@master
       with:
-        oss-fuzz-project-name: Cirq
+        oss-fuzz-project-name: cirq
         language: python
         fuzz-seconds: 600
         output-sarif: true