Remove instructions for Spark 2

Author: szarnyasg

README.md

@@ -36,7 +36,7 @@ You can build the JAR with both Maven and SBT.
     sbt assembly
     ```
 
-    :warning: When using SBT, change the path of the JAR file in the instructions provided in the README (`target/ldbc_snb_datagen_${PLATFORM_VERSION}-${DATAGEN_VERSION}.jar` -> `./target/scala-2.11/ldbc_snb_datagen-assembly-${DATAGEN_VERSION}.jar`).
+    :warning: When using SBT, change the path of the JAR file in the instructions provided in the README (`target/ldbc_snb_datagen_${PLATFORM_VERSION}-${DATAGEN_VERSION}.jar` -> `./target/scala-2.12/ldbc_snb_datagen-assembly-${DATAGEN_VERSION}.jar`).
 
 ### Install Python tools
 

tools/emr/README.md

@@ -56,15 +56,12 @@ To use spot instances, add the `--use-spot` argument:
 
 ### Using a different Spark / EMR version
 
-
-
-We use EMR 6.3.0 by default, which contains Spark 3.1. You can use a different version by specifying it with the `--emr-version` option. 
-EMR 5.33.0 is the recommended EMR version to be used with Spark 2.4.
-Make sure that you have uploaded the right JAR first!
+We use EMR 6.3.0 by default, which packages Spark 3.1. You can use a different version by specifying it with the `--emr-version` option.
+Make sure that you have uploaded the right JAR first.
 
 ```bash
-PLATFORM_VERSION=2.11_spark2.4
-./tools/emr/submit_datagen_job.py --bucket ${BUCKET_NAME} --platform-version ${PLATFORM_VERSION} --emr-release emr-5.33.0 ${JOB_NAME} ${SCALE_FACTOR} csv raw
+PLATFORM_VERSION=2.12_spark3.1
+./tools/emr/submit_datagen_job.py --bucket ${BUCKET_NAME} --platform-version ${PLATFORM_VERSION} --emr-release emr-6.2.0 ${JOB_NAME} ${SCALE_FACTOR} csv raw
 ```
 
 ### Using a parameter file

tools/emr/submit_datagen_job.py

@@ -238,13 +238,13 @@ def submit_datagen_job(name,
                         help='EC2 key name for SSH connection')
     parser.add_argument('--platform-version',
                         default=defaults['platform_version'],
-                        help='The spark platform the JAR is compiled for formatted like {scala.compat.version}_spark{spark.compat.version}, e.g. 2.11_spark2.4, 2.12_spark3.1')
+                        help='The spark platform the JAR is compiled for formatted like {scala.compat.version}_spark{spark.compat.version}, e.g. 2.12_spark3.1')
     parser.add_argument('--version',
                         default=defaults['version'],
                         help='LDBC SNB Datagen library version')
     parser.add_argument('--emr-release',
                         default=defaults['emr_release'],
-                        help='The EMR release to use. E.g emr-5.33.0, emr-6.3.0')
+                        help='The EMR release to use. E.g. emr-6.3.0')
     parser.add_argument('-y', '--yes',
                         default=defaults['yes'],
                         action='store_true',