GitHub Actions: improve naming and location of files

Just to make things a little more consistent.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

.github/workflows/linux-trusty-5.12.yml

@@ -14,7 +14,7 @@ jobs:
     - name: run build
       run: |
         cd ..
-        bash -x subsurface/.github/workflows/in-container-build.sh
+        bash -x subsurface/.github/workflows/scripts/linux-in-container-build.sh
 
     - name: create CI release
       uses: ./.github/actions/release

.github/workflows/windows.yml

@@ -30,7 +30,7 @@ jobs:
     - name: run build
       run: |
         cd /win
-        bash -x subsurface/.github/workflows/windows-in-container-build.sh 2>&1 | tee build.log
+        bash -x subsurface/.github/workflows/scripts/windows-in-container-build.sh 2>&1 | tee build.log
         grep "Built target installer" build.log
 
     - name: create CI release