ninja: Remove not wanted jar from src artifacts (#158)

* Remove not wanted jar from src artifacts

* Move the documentation to a better section

* Update readme
diff --git a/DEV-README.md b/DEV-README.md
index 7e6f587..63e39fb 100644
--- a/DEV-README.md
+++ b/DEV-README.md
@@ -56,10 +56,18 @@
 
 Cassandra Analytics will build for Spark 3 and Scala 2.12 by default.
 
+The `gradle-wrapper.jar` file is not being distributed as part of the sources packages.
+In order to build from sources, that jar needs to be generated by running this command with
+your system gradle:
+```shell
+gradle wrapper
+```
+
 Navigate to the top-level directory for this project:
 
 ```shell
-./gradlew clean assemble
+./gradlew clean assemble -PartifactType=common
+./gradlew assemble -PartifactType=spark
 ```
 
 ### Spark 3 and Scala 2.12
diff --git a/build.gradle b/build.gradle
index d9fe346..396806a 100644
--- a/build.gradle
+++ b/build.gradle
@@ -285,6 +285,7 @@
       include 'build.gradle'
       exclude '**/.gradle/**'
       exclude 'gradle/wrapper/gradle-wrapper.jar'
+      exclude 'scripts/.mvn/wrapper/maven-wrapper.jar'
       exclude '**.idea/**'
       exclude 'bin/**'
       exclude 'dependencies/**'