build: Move CMAKE_SKIP_RPATH from CMake to Guix script

Remove hardcoded CMAKE_SKIP_INSTALL_RPATH setting from CMakeLists.txt and add it as a CMake configuration option in the Guix build script. This makes the build system more portable by keeping build-environment-specific settings in the build scripts rather than hardcoded in the CMake configuration.

Changes:
- Remove set(CMAKE_SKIP_INSTALL_RPATH TRUE) from CMakeLists.txt
- Add -DCMAKE_SKIP_RPATH=TRUE to Guix build script CONFIGFLAGS

This addresses the feedback from hebasto in bitcoin#33247 (comment)

Author: 151henry151

CMakeLists.txt

@@ -630,7 +630,6 @@ if(CMAKE_SYSTEM_NAME STREQUAL "NetBSD")
   set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
 else()
   set(CMAKE_SKIP_BUILD_RPATH TRUE)
-  set(CMAKE_SKIP_INSTALL_RPATH TRUE)
 endif()
 add_subdirectory(test)
 add_subdirectory(doc)

contrib/guix/libexec/build.sh

@@ -206,7 +206,7 @@ mkdir -p "$OUTDIR"
 ###########################
 
 # CONFIGFLAGS
-CONFIGFLAGS="-DREDUCE_EXPORTS=ON -DBUILD_BENCH=OFF -DBUILD_GUI_TESTS=OFF -DBUILD_FUZZ_BINARY=OFF"
+CONFIGFLAGS="-DREDUCE_EXPORTS=ON -DBUILD_BENCH=OFF -DBUILD_GUI_TESTS=OFF -DBUILD_FUZZ_BINARY=OFF -DCMAKE_SKIP_RPATH=TRUE"
 
 # CFLAGS
 HOST_CFLAGS="-O2 -g"