Templates: Remove `sponge` from the build system.
Templates: Remove `sponge` from the build system.

This is now upstream in common, 4dbf5c44f5e1b465102d15da7918a2ea7b3f0c98.

smaccm/camkes-tool,smaccm/camkes-tool,smaccm/camkes-tool,agacek/camkes-tool,smaccm/camkes-tool,agacek/camkes-tool,agacek/camkes-tool