Update workflow to use GITHUB_WORKSPACE

It was pointed out the GITHUB_WORKSPACE points to the container path of
the workspace, so we can use it instead of hardcoding the
__w/openssl/openssl path

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from #22726)

.github/workflows/interop-tests.yml

@@ -22,19 +22,21 @@ jobs:
       COMPONENT: ${{ matrix.COMPONENT }}
     steps:
       - uses: actions/checkout@v4
+      - name: Display environment
+        run: export
       - name : Install needed tools
         run: |
           dnf -y install perl gcc rpmdevtools dnf-utils make tmt-all beakerlib \
                  fips-mode-setup crypto-policies-scripts
       - name: install interop tests
         run: |
-          cd /__w/openssl/openssl
+          cd ${GITHUB_WORKSPACE}
           git clone --branch=openssl --depth=1 https://gitlab.com/redhat-crypto/tests/interop.git
       - name: build openssl as an rpm
         run: |
           mkdir -p /build/SPECS && cd /build && echo -e "%_topdir /build\n%_lto_cflags %{nil}" >~/.rpmmacros && rpmdev-setuptree
-          cd /build && cp /__w/openssl/openssl/interop/openssl.spec SPECS/ && \
-          cd SPECS/ && source /__w/openssl/openssl/VERSION.dat && \
+          cd /build && cp ${GITHUB_WORKSPACE}/interop/openssl.spec SPECS/ && \
+          cd SPECS/ && source ${GITHUB_WORKSPACE}/VERSION.dat && \
           sed -i "s/^Version: .*\$/Version: $MAJOR.$MINOR.$PATCH/" openssl.spec && \
           sed -i 's/^Release: .*$/Release: dev/' openssl.spec
           yum-builddep -y /build/SPECS/openssl.spec # just for sure nothing is missing