Override version of shared convention plugins

To your sidenote: I tried without io.spring.dependency-management but then I have issues in the projects with resolving dependencies managed by Spring.

Of course you cannot simply remove it. You need to replace it with the built-in BOM handling like doing implementation(platform(<thebomhere>)) as is also documented in the Spring Boot documentation.

mavarazo/mcve-conventions

Unfortunately, this is not buildable, as it does not contain repositories, hence it does not really fulfill the "C"omplete of “MCVE”. :wink:
And after fixing that mavarazo/mcve-project also was not usable as it did not find the dependencies in mavenLocal()
But after fixing those, I could have a look.

While using mavenLocal() is bad of course, but I assume it is just for the sake of the “MCVE”.
Givent that, it is like I described, just add an according constraint.

Add this to foo/build.gradle.kts and you get 3.2.0:

buildscript {
    dependencies {
        constraints {
            classpath("org.springframework.boot:spring-boot-gradle-plugin:3.2.0")
        }
    }
}