CI: build: disable cache of external toolchain/sdk

Our buildbot build a different external toolchain/sdk for each build.
This cause the idea of using the tar hash to cache it broken and wrong.
This makes the github cache bloated and remove space for ccache cache.

Drop cache for external toolchain/sdk as the feature is broken and cause
problems to ccache cache.

Signed-off-by: Christian Marangi <[email protected]>

.github/workflows/build.yml

@@ -198,13 +198,11 @@ jobs:
           if curl $SUMS_FILE | grep -q ".*openwrt-toolchain.*tar.xz"; then
             TOOLCHAIN_STRING="$( curl $SUMS_FILE | grep ".*openwrt-toolchain.*tar.xz")"
             TOOLCHAIN_FILE=$(echo "$TOOLCHAIN_STRING" | sed -n -e 's/.*\(openwrt-toolchain.*\).tar.xz/\1/p')
-            TOOLCHAIN_SHA256=$(echo "$TOOLCHAIN_STRING" | cut -d ' ' -f 1)
             
             echo "toolchain-type=external_toolchain" >> $GITHUB_OUTPUT
           elif curl $SUMS_FILE | grep -q ".*openwrt-sdk.*tar.xz"; then
             TOOLCHAIN_STRING="$( curl $SUMS_FILE | grep ".*openwrt-sdk.*tar.xz")"
             TOOLCHAIN_FILE=$(echo "$TOOLCHAIN_STRING" | sed -n -e 's/.*\(openwrt-sdk.*\).tar.xz/\1/p')
-            TOOLCHAIN_SHA256=$(echo "$TOOLCHAIN_STRING" | cut -d ' ' -f 1)
 
             echo "toolchain-type=external_sdk" >> $GITHUB_OUTPUT
           else
@@ -212,17 +210,8 @@ jobs:
           fi
 
           echo "TOOLCHAIN_FILE=$TOOLCHAIN_FILE" >> "$GITHUB_ENV"
-          echo "TOOLCHAIN_SHA256=$TOOLCHAIN_SHA256" >> "$GITHUB_ENV"
           echo "TOOLCHAIN_PATH=$TOOLCHAIN_PATH" >> "$GITHUB_ENV"
 
-      - name: Cache external toolchain/sdk
-        if: inputs.build_toolchain == false && steps.parse-toolchain.outputs.toolchain-type != 'internal'
-        id: cache-external-toolchain
-        uses: actions/cache@v3
-        with:
-          path: openwrt/${{ env.TOOLCHAIN_FILE }}
-          key: ${{ env.TOOLCHAIN_FILE }}-${{ steps.parse-toolchain.outputs.toolchain-type }}-${{ env.TOOLCHAIN_SHA256 }}
-
       - name: Cache ccache
         uses: actions/cache@v3
         with:
@@ -232,7 +221,7 @@ jobs:
             ccache-kernel-${{ env.TARGET }}/${{ env.SUBTARGET }}-
 
       - name: Download external toolchain/sdk
-        if: inputs.build_toolchain == false && steps.cache-external-toolchain.outputs.cache-hit != 'true' && steps.parse-toolchain.outputs.toolchain-type != 'internal'
+        if: inputs.build_toolchain == false && steps.parse-toolchain.outputs.toolchain-type != 'internal'
         shell: su buildbot -c "sh -e {0}"
         working-directory: openwrt
         run: |
@@ -284,7 +273,7 @@ jobs:
             --config ${{ env.TARGET }}/${{ env.SUBTARGET }}
 
       - name: Adapt external sdk to external toolchain format
-        if: inputs.build_toolchain == false && steps.parse-toolchain.outputs.toolchain-type == 'external_sdk' && steps.cache-external-toolchain.outputs.cache-hit != 'true'
+        if: inputs.build_toolchain == false && steps.parse-toolchain.outputs.toolchain-type == 'external_sdk'
         shell: su buildbot -c "sh -e {0}"
         working-directory: openwrt
         run: |