Put GHC and Cabal into path in integration script.

We need this to happen because our `examples` test suite needs access to
the built executable.

.github/workflows/haskell-ci.yml

@@ -1,17 +1,3 @@
-# This GitHub workflow config has been generated by a script via
-#
-#   haskell-ci 'github' '--no-cabal-check' '--installed' '-all' 'cabal-prettify.cabal'
-#
-# To regenerate the script (for example after adjusting tested-with) run
-#
-#   haskell-ci regenerate
-#
-# For more information, see https://github.com/haskell-CI/haskell-ci
-#
-# version: 0.16.6
-#
-# REGENDATA ("0.16.6",["github","--no-cabal-check","--installed","-all","cabal-prettify.cabal"])
-#
 name: Haskell-CI
 on:
   - push
@@ -48,6 +34,7 @@ jobs:
           curl -sL https://downloads.haskell.org/ghcup/0.1.19.2/x86_64-linux-ghcup-0.1.19.2 > "$HOME/.ghcup/bin/ghcup"
           chmod a+x "$HOME/.ghcup/bin/ghcup"
           "$HOME/.ghcup/bin/ghcup" install ghc "$HCVER" || (cat "$HOME"/.ghcup/logs/*.* && false)
+          "$HOME/.ghcup/bin/ghcup" set ghc "$HCVER"
           "$HOME/.ghcup/bin/ghcup" install cabal 3.10.1.0 || (cat "$HOME"/.ghcup/logs/*.* && false)
         env:
           HCKIND: ${{ matrix.compilerKind }}
@@ -56,6 +43,7 @@ jobs:
       - name: Set PATH and environment variables
         run: |
           echo "$HOME/.cabal/bin" >> $GITHUB_PATH
+          echo "$HOME/.ghcup/bin" >> $GITHUB_PATH
           echo "LANG=C.UTF-8" >> "$GITHUB_ENV"
           echo "CABAL_DIR=$HOME/.cabal" >> "$GITHUB_ENV"
           echo "CABAL_CONFIG=$HOME/.cabal/config" >> "$GITHUB_ENV"