tests: remove previous fuzz testing

We now use https://github.com/google/fuzztest (see previous commits).
And the test was also failing to build
(https://github.com/PX4/PX4-Autopilot/actions/workflows/cflite_batch.yml)

This reverts these commits:
- 9eda5b373c
- 2cbc993976
- be0a5b4b32

.github/workflows/cflite_batch.yml

@@ -1,34 +0,0 @@
-name: ClusterFuzzLite batch fuzzing
-on:
-  schedule:
-    - cron: '0 6 * * *'  # UTC 6am every day.
-permissions: read-all
-jobs:
-  BatchFuzzing:
-    runs-on: ubuntu-latest
-    strategy:
-      fail-fast: false
-      matrix:
-        sanitizer:
-        - address
-        - undefined
-        - memory
-    steps:
-    - name: Build Fuzzers (${{ matrix.sanitizer }})
-      id: build
-      uses: google/clusterfuzzlite/actions/build_fuzzers@v1
-      with:
-        sanitizer: ${{ matrix.sanitizer }}
-    - name: Run Fuzzers (${{ matrix.sanitizer }})
-      id: run
-      uses: google/clusterfuzzlite/actions/run_fuzzers@v1
-      with:
-        github-token: ${{ secrets.GITHUB_TOKEN }}
-        fuzz-seconds: 1800 # 30 mins
-        mode: 'batch'
-        sanitizer: ${{ matrix.sanitizer }}
-        # Optional but recommended: For storing certain artifacts from fuzzing.
-        # See later section on "Git repo for storage".
-        # storage-repo: https://${{ secrets.PERSONAL_ACCESS_TOKEN }}@github.com/OWNER/STORAGE-REPO-NAME.git
-        # storage-repo-branch: main   # Optional. Defaults to "main"
-        # storage-repo-branch-coverage: gh-pages  # Optional. Defaults to "gh-pages".