Update CMakeLists.txt

Pin to specific C++ version now that the KLL fix is released

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4c56d33..d56c0b0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -116,7 +116,7 @@
 include(ExternalProject)
 ExternalProject_Add(datasketches
   GIT_REPOSITORY https://github.com/apache/datasketches-cpp.git
-  GIT_TAG master
+  GIT_TAG 5.0.1
   GIT_SHALLOW true
   GIT_SUBMODULES ""
   INSTALL_DIR /tmp/datasketches