re2: update to current main

To include this commit:
google/re2@9ebe4a2

Which should fix the CI error:
CMake Error at /home/runner/work/MAVSDK/MAVSDK/build/release/third_party/install/lib/cmake/re2/re2Config.cmake:15 (message):
  File or directory /include referenced by variable re2_INCLUDE_DIR does not
  exist !

third_party/re2/CMakeLists.txt

@@ -27,7 +27,8 @@ endforeach()
 
 ExternalProject_add(
     re2
-    URL https://github.com/google/re2/archive/2023-11-01.tar.gz
+    GIT_REPOSITORY https://github.com/google/re2
+    GIT_TAG b84e3ff189980a33d4a0c6fa1201aa0b3b8bab4a
     PREFIX re2
     CMAKE_ARGS "${CMAKE_ARGS}"
     )