ci: enable CI_BUILD automatically if environment variable CI is true (#22312)

Having to specify CI_BUILD for every CI job requires boilerplate. More
importantly, it's easy to forget to enable CI_BUILD, as seen by
8a20f9f98a. It's simpler to remember to
turn CI_BUILD off when a job errors instead of remembering that every
new job should have CI_BUILD on.

.github/workflows/build.yml

@@ -67,7 +67,7 @@ jobs:
         run: make deps
 
       - name: Build
-        run: make CMAKE_FLAGS="-D CI_BUILD=ON -D CMAKE_INSTALL_PREFIX:PATH=$INSTALL_PREFIX"
+        run: make CMAKE_FLAGS="-D CMAKE_INSTALL_PREFIX:PATH=$INSTALL_PREFIX"
 
       - name: Install
         run: make install

.github/workflows/release.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Build release
         id: build
         run: |
-          CC=gcc-10 make CMAKE_BUILD_TYPE=${NVIM_BUILD_TYPE} CMAKE_EXTRA_FLAGS="-DCMAKE_INSTALL_PREFIX:PATH="
+          CC=gcc-10 make CMAKE_BUILD_TYPE=${NVIM_BUILD_TYPE} CMAKE_EXTRA_FLAGS="-DCI_BUILD=OFF -DCMAKE_INSTALL_PREFIX:PATH="
           printf 'version<<END\n' >> $GITHUB_OUTPUT
           ./build/bin/nvim --version | head -n 3 >> $GITHUB_OUTPUT
           printf 'END\n' >> $GITHUB_OUTPUT
@@ -127,7 +127,7 @@ jobs:
           cmake --build .deps
       - name: build package
         run: |
-          cmake -B build -G Ninja -DCMAKE_BUILD_TYPE='RelWithDebInfo'
+          cmake -B build -G Ninja -DCMAKE_BUILD_TYPE='RelWithDebInfo' -D CI_BUILD=OFF
           cmake --build build --target package
       - uses: actions/upload-artifact@v3
         with:

.github/workflows/test.yml

@@ -88,11 +88,13 @@ jobs:
           version: latest
           args: --check runtime/
 
+      - if: success() || failure() && steps.abort_job.outputs.status == 'success'
+        name: configure
+        run: cmake -B build -G Ninja -D CI_BUILD=OFF
+
       - if: success() || failure() && steps.abort_job.outputs.status == 'success'
         name: luacheck
-        run: |
-          cmake -B build -G Ninja
-          cmake --build build --target lintlua-luacheck
+        run: cmake --build build --target lintlua-luacheck
 
       - if: success() || failure() && steps.abort_job.outputs.status == 'success'
         name: lintsh
@@ -198,7 +200,7 @@ jobs:
 
       - name: Build
         run: |
-          cmake -B build -G Ninja -D CI_BUILD=ON -D CMAKE_INSTALL_PREFIX:PATH=$INSTALL_PREFIX ${{ matrix.flags }}
+          cmake -B build -G Ninja -D CMAKE_INSTALL_PREFIX:PATH=$INSTALL_PREFIX ${{ matrix.flags }}
           cmake --build build
 
       - if: "!cancelled()"
@@ -318,7 +320,7 @@ jobs:
 
       - name: Build
         run: |
-          cmake -B build -G Ninja -D CMAKE_BUILD_TYPE='RelWithDebInfo' -D CI_BUILD=ON
+          cmake -B build -G Ninja -D CMAKE_BUILD_TYPE='RelWithDebInfo'
           cmake --build build
 
       - name: Install test deps