linux-pipewire: Require Gio 2.76

Subsequent commits use g_clear_fd() added in GLib 2.76.

plugins/linux-pipewire/CMakeLists.txt

@@ -7,7 +7,7 @@ if(NOT ENABLE_PIPEWIRE)
 endif()
 
 find_package(PipeWire 0.3.33 REQUIRED)
-find_package(Gio REQUIRED)
+find_package(Gio 2.76 REQUIRED)
 find_package(Libdrm REQUIRED)
 get_target_property(libdrm_include_directories Libdrm::Libdrm INTERFACE_INCLUDE_DIRECTORIES)