Use ":// " pattern to detect URLs instead of only matching http/https schemes

Co-authored-by: JohnAmadis <17320783+JohnAmadis@users.noreply.github.com>

Author: Copilot

CMakeLists.txt

@@ -20,7 +20,7 @@ option(DMBOOT_EMULATION "Enable Renode emulation mode" OFF)
 # Convert relative manifest path to absolute so it remains valid when the
 # working directory changes during the build (e.g. dmf-get is invoked from a
 # different directory than where cmake was originally run).
-if(DMBOOT_MANIFEST_URL AND NOT DMBOOT_MANIFEST_URL MATCHES "^https?://")
+if(DMBOOT_MANIFEST_URL AND NOT DMBOOT_MANIFEST_URL MATCHES "://")
     get_filename_component(DMBOOT_MANIFEST_URL "${DMBOOT_MANIFEST_URL}" ABSOLUTE BASE_DIR "${CMAKE_BINARY_DIR}")
     message(STATUS "Resolved manifest path to absolute: ${DMBOOT_MANIFEST_URL}")
 endif()