Use ppbt toolchain when building.

Instead of having relenv maintain, build and distribute it's own
toolchain use ppbt. The benefits of ppbt are that the toolchain comes
packaged in python wheel. Also we'll only need to build ppbt when
changes take place to the toolchain instead of every relenv release.

Author: dwoz

.github/workflows/ci.yml

@@ -51,12 +51,6 @@ jobs:
             deleted:
               - deleted:
                 - '**'
-            toolchain:
-              - added|modified:
-                - '.github/workflows/*toolchain*.yml'
-                - 'relenv/toolchain.py'
-                - 'relenv/_toolchain/**'
-
   pre-commit:
     name: Pre-Commit
     uses: ./.github/workflows/pre-commit-action.yml
@@ -75,20 +69,11 @@ jobs:
       kind: "${{ inputs.kind }}"
       cmd: "${{ inputs.package_command }}"
 
-  toolchain:
-    name: Toolchain Builds
-    uses: ./.github/workflows/toolchain-action.yml
-    needs:
-      - get-changed-files
-    with:
-      changed-files: ${{ needs.get-changed-files.outputs.changed-files }}
-
   build-native:
     name: Python Native Builds
     uses: ./.github/workflows/build-native-action.yml
     needs:
       - get-changed-files
-      - toolchain
     with:
       changed-files: ${{ needs.get-changed-files.outputs.changed-files }}
 
@@ -104,7 +89,6 @@ jobs:
   #  uses: ./.github/workflows/build-action.yml
   #  needs:
   #    - get-changed-files
-  #    - toolchain
   #    - build-native
   #  with:
   #    changed-files: ${{ needs.get-changed-files.outputs.changed-files }}
@@ -138,16 +122,6 @@ jobs:
     with:
       version: "${{ needs.build-python-package.outputs.version }}"
 
-  upload-toolchain-artifacts:
-    name: Deploy Toolchain
-    if: ${{ inputs.kind == 'release' && success() }}
-    uses: ./.github/workflows/deploy-toolchain-action.yml
-    needs:
-      - build-python-package
-      - toolchain
-    with:
-      version: "${{ needs.build-python-package.outputs.version }}"
-
   deploy-python-package:
     name: Deploy Python Package
     uses: ./.github/workflows/deploy-package-action.yml
@@ -159,7 +133,6 @@ jobs:
       - build-python-package
       - test-fips
       - upload-build-artifacts
-      - upload-toolchain-artifacts
 
   create-release:
     name: Create Github Release
@@ -180,13 +153,11 @@ jobs:
     if: always()
     needs:
       - pre-commit
-      - toolchain
       - build-native
       #- build-cross
       - test
       - docs
       - upload-build-artifacts
-      - upload-toolchain-artifacts
       - deploy-python-package
       - create-release
     steps: