Upgrade Iceberg version for regtests and docs

Author: liamzwbao

regtests/setup.sh

@@ -31,7 +31,7 @@ if [ -z "${SPARK_HOME}" ]; then
 fi
 SPARK_CONF="${SPARK_HOME}/conf/spark-defaults.conf"
 DERBY_HOME="/tmp/derby"
-ICEBERG_VERSION="1.7.1"
+ICEBERG_VERSION="1.8.1"
 export PYTHONPATH="${SPARK_HOME}/python/:${SPARK_HOME}/python/lib/py4j-0.10.9.7-src.zip:$PYTHONPATH"
 
 # Ensure binaries are downloaded locally

regtests/t_pyspark/src/iceberg_spark.py

@@ -72,7 +72,7 @@ def __enter__(self):
     """Initial method for Iceberg Spark session. Creates a Spark session with specified configs.
     """
     packages = [
-      "org.apache.iceberg:iceberg-spark-runtime-3.5_2.12:1.7.1",
+      "org.apache.iceberg:iceberg-spark-runtime-3.5_2.12:1.8.1",
       "org.apache.hadoop:hadoop-aws:3.4.0",
       "software.amazon.awssdk:bundle:2.23.19",
       "software.amazon.awssdk:url-connection-client:2.23.19",

site/content/in-dev/unreleased/quickstart.md

@@ -280,7 +280,7 @@ _Note: the credentials provided here are those for our principal, not the root c
 
 ```shell
 bin/spark-shell \
---packages org.apache.iceberg:iceberg-spark-runtime-3.5_2.12:1.7.1,org.apache.hadoop:hadoop-aws:3.4.0 \
+--packages org.apache.iceberg:iceberg-spark-runtime-3.5_2.12:1.8.1,org.apache.hadoop:hadoop-aws:3.4.0 \
 --conf spark.sql.extensions=org.apache.iceberg.spark.extensions.IcebergSparkSessionExtensions \
 --conf spark.sql.catalog.quickstart_catalog.warehouse=quickstart_catalog \
 --conf spark.sql.catalog.quickstart_catalog.header.X-Iceberg-Access-Delegation=vended-credentials \