MSAN testing falsely reported a use-of-uninitialized-value when running poc_test, the cause was calling c_str on a string passed into wiredtiger_open.

The log for the test is here: https://spruce.mongodb.com/task/wiredtiger_rhel80_make_check_msan_test_patch_03aea58a2640ba6a048f6eee2a7b7d52d8809d70_601a35733627e0294b197924_21_02_03_05_32_54/logs?execution=0

Viewing online discussion about this it appears we need to compile the standard library with memory sanitizer. More info here:
https://github.com/google/sanitizers/wiki/MemorySanitizerLibcxxHowTo

While we can fix the potential causes in the test framework it would be good to implement a long term solution.

Update:
We'll disable memory sanitized testing for WiredTiger c++ code. To do so I believe all we need to do is pull out CXXFLAGS='-fsanitize=memory' from the evergreen.yml. To test add the following code to test/poc.cxx main.c and either do an evergreen patch build or compile with memory sanitizer.

    std::string err_string = "error";
    std::cout << "MSAN error: "<< err_string.c_str() << std::endl;