[guix] Removed ThirdParty/collection submodule.

.gitmodules

@@ -7,6 +7,3 @@
 [submodule "ThirdParty/bilke/cmake-modules"]
 	path = ThirdParty/bilke/cmake-modules
 	url = https://github.com/bilke/cmake-modules.git
-[submodule "ThirdParty/collection"]
-	path = ThirdParty/collection
-	url = https://gitlab.opengeosys.org/ogs/libs/collection.git

.guix/modules/ogs-package.scm

@@ -45,7 +45,7 @@
 (define vcs-file?
   ;; Return true if the given file is under version control.
   (or (git-predicate "../..") ; (current-source-directory)
-      (const #t)))            ;not in a Git checkout
+      (const #t)))            ; not in a Git checkout
 
 (define-public ogs
   (package

scripts/cmake/CMakeSetup.cmake

@@ -16,13 +16,6 @@ if(WIN32 AND (NOT "${CMAKE_GENERATOR}" MATCHES "Visual Studio")
     message(FATAL_ERROR "Wheels only build in Visual Studio!")
 endif()
 
-set(_collection ${PROJECT_SOURCE_DIR}/ThirdParty/collection)
-# If submodules in ThirdParty/collection are initialized and this is a Guix
-# build use submodule as CPM sources.
-if(EXISTS ${_collection}/ogs/libs/xdmf/CMakeLists.txt AND GUIX_BUILD)
-    include(${_collection}/Setup.cmake)
-endif()
-
 # Set additional CMake modules path
 set(CMAKE_MODULE_PATH
     ${CMAKE_MODULE_PATH} "${PROJECT_SOURCE_DIR}/scripts/cmake"