The package's name "MODULE_GRBL13.2" in library.properties should be "MODULE_GRBL_13.2" (underline instead of space before 13.2).
So
download M5Stack
unzip it
edit file "library.properties", line to "depends=M5Family,M5Module-4Relay,MODULE_GRBL_13.2,M5_BMM150"
zip it and install zipped library
restart IDE
update now performed flawless