Explicitly state 'zlib' and 'rapidjson' bundling status

Both are set to 'bundled' by default !

We really want to avoid bundling zlib.
On top of that, there is currently a problem with the bundled zlib, which results in a linker error during compilation.

We want to un-bundle rapidjson too, but:
| -- Performing Test HAVE_RAPIDJSON_WITH_STD_REGEX
| -- Performing Test HAVE_RAPIDJSON_WITH_STD_REGEX - Failed
| CMake Error at cmake/rapidjson.cmake:114 (MESSAGE):
|   System rapidjson lacks some fixes required for support of regular
|   expressions.  See extra/RAPIDJSON-README for details.
| Call Stack (most recent call first):
|   CMakeLists.txt:1952 (MYSQL_CHECK_RAPIDJSON)
| -- Configuring incomplete, errors occurred!
needs further investigation.

mysql8.0.spec

@@ -540,6 +540,8 @@ cp %{SOURCE2} %{SOURCE3} %{SOURCE10} %{SOURCE11} %{SOURCE12} \
 %endif
          -DWITH_ROUTER=OFF \
          -DWITH_SYSTEM_LIBS=ON \
+         -DWITH_ZLIB=system \
+         -DWITH_RAPIDJSON=bundled \
          -DWITH_MECAB=system \
          -DWITH_FIDO=system \
          -DWITH_BOOST=boost \