Remove unused env vars

Author: hsiang-c

.github/workflows/iceberg_spark_test.yml

@@ -73,7 +73,7 @@ jobs:
         run: |
           cd apache-iceberg
           rm -rf /root/.m2/repository/org/apache/parquet # somehow parquet cache requires cleanups
-          ENABLE_COMET=true ENABLE_COMET_SHUFFLE=true ./gradlew -DsparkVersions=${{ matrix.spark-version.short }} -DscalaVersion=${{ matrix.scala-version }} -DflinkVersions= -DkafkaVersions= \
+          ./gradlew -DsparkVersions=${{ matrix.spark-version.short }} -DscalaVersion=${{ matrix.scala-version }} -DflinkVersions= -DkafkaVersions= \
             :iceberg-spark:iceberg-spark-${{ matrix.spark-version.short }}_${{ matrix.scala-version }}:check \
             :iceberg-spark:iceberg-spark-extensions-${{ matrix.spark-version.short }}_${{ matrix.scala-version }}:check \
             :iceberg-spark:iceberg-spark-runtime-${{ matrix.spark-version.short }}_${{ matrix.scala-version }}:check \