Can't setup spongeForgeVersion

[JimiIT92]

Hi, I'm trying to setup the plugin to use a stable Sponge release with API 7.2.0.
So I'm doing this in the build.gradle file

spongestart{
    eula true
    spongeForgeVersion '1.12.2-2838-7.2.0'
}

However when I run the server this error comes up

1.12.2-2838-7.2.0: Is definally not a valid version string

So how can I set the plugin to use this specific version of Sponge?