ci: update from Node.js 16 to Node.js 18

Node.js 16 is no longer supported, so we can drop support for it as
well.

This also means updating a whole lot of GitHub Actions versions, because
they were updated to work on Node.js 20 instead. For most actions this
should be a relatively small change, but the upload-aftifact action has
had some major changes (which should generally improve things a lot).

.github/workflows/build-macos.yml

@@ -35,12 +35,12 @@ jobs:
         with:
           submodules: true
       - name: Install Go
-        uses: actions/setup-go@v4
+        uses: actions/setup-go@v5
         with:
           go-version: '1.21'
           cache: true
       - name: Restore LLVM source cache
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         id: cache-llvm-source
         with:
           key: llvm-source-17-${{ matrix.os }}-v1
@@ -54,7 +54,7 @@ jobs:
         if: steps.cache-llvm-source.outputs.cache-hit != 'true'
         run: make llvm-source
       - name: Save LLVM source cache
-        uses: actions/cache/save@v3
+        uses: actions/cache/save@v4
         if: steps.cache-llvm-source.outputs.cache-hit != 'true'
         with:
           key: ${{ steps.cache-llvm-source.outputs.cache-primary-key }}
@@ -65,7 +65,7 @@ jobs:
             llvm-project/lld/include
             llvm-project/llvm/include
       - name: Restore LLVM build cache
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         id: cache-llvm-build
         with:
           key: llvm-build-17-${{ matrix.os }}-v1
@@ -83,13 +83,13 @@ jobs:
           make llvm-build
           find llvm-build -name CMakeFiles -prune -exec rm -r '{}' \;
       - name: Save LLVM build cache
-        uses: actions/cache/save@v3
+        uses: actions/cache/save@v4
         if: steps.cache-llvm-build.outputs.cache-hit != 'true'
         with:
           key: ${{ steps.cache-llvm-build.outputs.cache-primary-key }}
           path: llvm-build
       - name: Cache wasi-libc sysroot
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         id: cache-wasi-libc
         with:
           key: wasi-libc-sysroot-${{ matrix.os }}-v1
@@ -116,7 +116,7 @@ jobs:
         # - have a double-zipped artifact when downloaded from the UI
         # - have a very slow artifact upload
         # We're doing the former here, to keep artifact uploads fast.
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: darwin-${{ matrix.goarch }}-double-zipped
           path: build/tinygo.darwin-${{ matrix.goarch }}.tar.gz
@@ -143,7 +143,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Install Go
-        uses: actions/setup-go@v4
+        uses: actions/setup-go@v5
         with:
           go-version: '1.21'
           cache: true