CDF-20156: fixup fatjar pom file

[dmivankov]

Currently
https://repo1.maven.org/maven2/com/cognite/spark/datasource/cdf-spark-datasource-fatjar_2.13/3.2.1044/cdf-spark-datasource-fatjar_2.13-3.2.1044.pom
includes

<dependencies>
  <dependency>
    <groupId>org.scala-lang</groupId>
    <artifactId>scala-library</artifactId>
    <version>2.13.8</version>
  </dependency>
  <dependency>
    <groupId>com.cognite.spark.datasource</groupId>
    <artifactId>cdf-spark-datasource_2.13</artifactId>
    <version>3.2.1044</version>
  </dependency>
  <dependency>
    <groupId>io.scalaland</groupId>
    <artifactId>chimney_2.13</artifactId>
    <version>0.5.3</version>
  </dependency>
</dependencies>

Which isn't expected, fatjar should have (almost) no dependencies.
The jar itself though contains all the classes and applies shading
as expected.
It is then possible that pulling fatjar from maven central would pull duplicated classes
and if non-fatjar unshaded versions are picked up or a mix with fatjar ones, the
datasource would runtime-crash when used for example in Spark in DataBricks.

Let's remove chimney from commonSettings and move to per-target dependencies.
And for main library, looks like the simplest way to both
have it as part of fatJar and not have it in pom is to patch generated pom.

As for scala-library keeping it as-is, older fatjar setup also had it,
so not investigating for now.

Verified pom contents by running fatJarShaded/publishLocal and inspecting pom
from filesystem.
And used fatJarShaded/assembly to generate fatjar and inspect with jar tf
to check that is has our classes and applies shading rules.
Did not yet verify in databricks, but even if this PR isn't enough to fix
running there it is still a step in the right directiion.

CDF-20156

[codecov]

Codecov Report

Merging #858 (89f485d) into master (d473c47) will not change coverage.
The diff coverage is n/a.

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