fix(ci): write bm-ci key to RUNNER_TEMP and derive .pub for bm-bootstrap

.github/workflows/e2e-baremetal.yml

@@ -44,9 +44,9 @@ jobs:
 
       - name: Install SSH Key
         run: |
-          install -m 0700 -d ~/.ssh
-          echo "${{ secrets.BM_SSH_PRIVATE_KEY }}" > ~/.ssh/bm-ci
-          chmod 0600 ~/.ssh/bm-ci
+          echo "${{ secrets.BM_SSH_PRIVATE_KEY }}" > "${RUNNER_TEMP}/bm-ci"
+          chmod 0600 "${RUNNER_TEMP}/bm-ci"
+          ssh-keygen -y -f "${RUNNER_TEMP}/bm-ci" > "${RUNNER_TEMP}/bm-ci.pub"
 
       - name: Build Artifacts
         run: |
@@ -82,7 +82,7 @@ jobs:
       - name: Run Bare-Metal E2E
         env:
           BM_CI_PASSWORD: ${{ secrets.BM_CI_PASSWORD }}
-          BM_SSH_KEY: /home/tf-user/.ssh/bm-ci
+          BM_SSH_KEY: ${{ runner.temp }}/bm-ci
           BM_EPDU_ENV: ${{ runner.temp }}/epdu.env
           SPX_EXTERNAL_POOL: ${{ env.SPINIFEX_CI_POOL }}
         run: |