[libc++] Run the LLDB data formatter tests after libc++'s own tests (#119028)

It makes more sense to start testing libc++ with the latest compiler and
only then to run the LLDB data formatter tests, since that provides more
signal than starting with the data formatter tests.

Author: ldionne

libcxx/utils/ci/run-buildbot

@@ -387,16 +387,16 @@ bootstrapping-build)
           -DLLVM_ENABLE_ASSERTIONS=ON \
           -DLLVM_LIT_ARGS="-sv --xunit-xml-output test-results.xml --timeout=1500 --time-tests"
 
-    step "Running the LLDB libc++ data formatter tests"
-    ${NINJA} -vC "${BUILD_DIR}" lldb-api-test-deps
-    ${BUILD_DIR}/bin/llvm-lit -sv --param dotest-args='--category libc++' "${MONOREPO_ROOT}/lldb/test/API"
-
     step "Running the libc++ and libc++abi tests"
     ${NINJA} -vC "${BUILD_DIR}" check-runtimes
 
     step "Installing libc++ and libc++abi to a fake location"
     ${NINJA} -vC "${BUILD_DIR}" install-runtimes
 
+    step "Running the LLDB libc++ data formatter tests"
+    ${NINJA} -vC "${BUILD_DIR}" lldb-api-test-deps
+    ${BUILD_DIR}/bin/llvm-lit -sv --param dotest-args='--category libc++' "${MONOREPO_ROOT}/lldb/test/API"
+
     ccache -s
 ;;
 generic-static)