chore(ci): fix benchmark matrix parameters generation

Previous implementation was done to please Zizmor and avoid
template-injection findings during analysis. This had a downside,
using env directive implies a double-interpolation that messes with
fromJSON() later and build badly formatted matrix parameters.

.github/workflows/benchmark_gpu_common.yml

@@ -122,31 +122,23 @@ jobs:
 
       - name: Set command output
         id: set_command
-        run: |
-          echo "command=${COMMAND_OUTPUT}" >> "${GITHUB_OUTPUT}"
-        env:
-          COMMAND_OUTPUT: ${{ toJSON(env.COMMAND) }}
+        run: | # zizmor: ignore[template-injection] this env variable is safe
+          echo "command=${{ toJSON(env.COMMAND) }}" >> "${GITHUB_OUTPUT}"
 
       - name: Set operation flavor output
         id: set_op_flavor
-        run: |
-          echo "op_flavor=${OP_FLAVOR_OUTPUT}" >> "${GITHUB_OUTPUT}"
-        env:
-          OP_FLAVOR_OUTPUT: ${{ toJSON(env.OP_FLAVOR) }}
+        run: | # zizmor: ignore[template-injection] this env variable is safe
+          echo "op_flavor=${{ toJSON(env.OP_FLAVOR) }}" >> "${GITHUB_OUTPUT}"
 
       - name: Set benchmark types output
         id: set_bench_type
-        run: |
-          echo "bench_type=${BENCH_TYPE_OUTPUT}" >> "${GITHUB_OUTPUT}"
-        env:
-          BENCH_TYPE_OUTPUT: ${{ toJSON(env.BENCH_TYPE) }}
+        run: | # zizmor: ignore[template-injection] this env variable is safe
+          echo "bench_type=${{ toJSON(env.BENCH_TYPE) }}" >> "${GITHUB_OUTPUT}"
 
       - name: Set parameters types output
         id: set_params_type
-        run: |
-          echo "params_type=${PARAMS_TYPE_OUTPUT}" >> "${GITHUB_OUTPUT}"
-        env:
-          PARAMS_TYPE_OUTPUT: ${{ toJSON(env.PARAMS_TYPE) }}
+        run: | # zizmor: ignore[template-injection] this env variable is safe
+          echo "params_type=${{ toJSON(env.PARAMS_TYPE) }}" >> "${GITHUB_OUTPUT}"
 
   setup-instance:
     name: Setup instance (cuda-${{ inputs.profile }}-benchmarks)