Fix compatibility for nested modules

[IgnatBeresnev]

Background

Ktor has many nested modules, which leads to the existence of multiple Gradle parent projects. By default, the dokkaHtmlMultiModule task is created for all parent projects.

So if there are nested modules and dokkaHtmlMultiModule is run, it means it will be executed for all parent projects, not just the root one, which in Gradle 8 leads to errors like the following:

Reason: Task ':dokkaHtmlMultiModule' uses this output of task ':sqldelight-compiler:dokkaHtmlMultiModule' without declaring an explicit or implicit dependency. This can lead to incorrect results being produced, depending on what order the tasks are executed.

This error could be observed after ktorio/ktor#3743 is merged.

For more details, see Kotlin/dokka#2954

Solution

Only run dokkaHtmlMultiModule for the root project by adding a semicolon in front of it. This way, it will not be called on any projects other than the root one, and so it will not lead to task dependency errors.