symlinked source directory trips up cmake server (CMAKE_HOME_DIRECTORY is set but incompatible with configured source directory value)

To reproduce:

cd /tmp
mkdir sources
touch sources/CMakeLists.txt
ln -s sources symlinked-sources
mkdir build
cd build
cmake /tmp/sources
cmake -E server --experimental --debug

[== "CMake Server" ==[
{"supportedProtocolVersions":[{"isExperimental":true,"major":1,"minor":0}],"type":"hello"}
]== "CMake Server" ==]

[== "CMake Server" ==[
{"buildDirectory":"/tmp/build","cookie":null,"generator":"Unix Makefiles","major":1,"protocolVersion":{"major":1},"sourceDirectory":"/tmp/symlinked-sources","type":"handshake"}
]== "CMake Server" ==]

[== "CMake Server" ==[
{"cookie":"","errorMessage":"Failed to activate protocol version: \"CMAKE_HOME_DIRECTORY\" is set but incompatible with configured source directory value.","inReplyTo":"handshake","type":"error"}
]== "CMake Server" ==]

I suggest to only compare canonical paths