[jenkins] Coverage bot: Remove cross-project-tests

[gulfem]

Summary

Directory coverage is recently enabled in https://reviews.llvm.org/D158703
The following file shows up at the top level because cross-project-tests is
also built in the coverage build:
cross-project-tests/debuginfo-tests/llvm-prettyprinters/gdb/llvm-support.cpp
This patch removes cross-project-tests from the project list.

zorg/jenkins/jobs/jobs/llvm-coverage

stages {
                       --cmake-flag="-DLLVM_TARGETS_TO_BUILD=host" \
                       --cmake-type=Release \
                       --projects "" \
                       --noinstall \
                       --noupload
 
                     python llvm-zorg/zorg/jenkins/monorepo_build.py lldb-cmake build \
                       --assertions \
-                      --projects="clang;lldb;cross-project-tests" \
+                      --projects="clang;lldb" \
                       --runtimes="libcxx;libcxxabi" \
                       --cmake-flag="-DPYTHON_LIBRARY=/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/libpython3.7.dylib" \
                       --cmake-flag="-DPYTHON_INCLUDE_DIR=/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/include/python3.7m" \
                       --cmake-flag="-DPYTHON_LIBRARY_DEBUG=/usr/local/Cellar/python/3.7.0/Frameworks/Python.framework/Versions/3.7/lib/libpython3.7.dylib" \
                       --cmake-flag="-DPYTHON_EXECUTABLE=/usr/local/Cellar/python/3.7.0/bin/python3.7" \
                       --cmake-flag="-DLLDB_USE_SYSTEM_DEBUGSERVER=ON" \
                       --cmake-flag="-DLLVM_BUILD_INSTRUMENTED_COVERAGE=ON" \
                       --cmake-flag="-DLLVM_PROFILE_MERGE_POOL_SIZE=1" \