chore(ci): Clear space at the start of the k8s e2e workflow (#21723)

We seem to be hitting cases where the workflow dies because it runs out of space. Example: https://github.com/vectordotdev/vector/actions/runs/11710738799/job/32617708471

Signed-off-by: Jesse Szwedko <[email protected]>

.github/workflows/k8s_e2e.yml

@@ -95,6 +95,7 @@ jobs:
             ~/.cargo/git
           key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
 
+      - run: sudo -E bash scripts/ci-free-disk-space.sh
       - run: sudo -E bash scripts/environment/bootstrap-ubuntu-20.04.sh
       - run: bash scripts/environment/prepare.sh
       - run: echo "::add-matcher::.github/matchers/rust.json"