Get rid of JDK8 in scripts, not supported anywhere anymore

build.xml

@@ -46,7 +46,7 @@
     -->
     <property name="java.default" value="11" />
     <!-- Not sure whether we need 17 below, at least jvm options were added some time ago for 17 -->
-    <property name="java.supported" value="1.8,11,17,22" />
+    <property name="java.supported" value="11,17,22" />
 
     <!-- directory details -->
     <property name="basedir" value="."/>

tools/bin/cassandra.in.sh

@@ -76,8 +76,6 @@ if [ -z $JAVA ] ; then
     exit 1;
 fi
 
-java_versions_supported=11,17,22
-
 # Determine the sort of JVM we'll be running on.
 java_ver_output=`"${JAVA:-java}" -version 2>&1`
 jvmver=`echo "$java_ver_output" | grep '[openjdk|java] version' | awk -F'"' 'NR==1 {print $2}' | cut -d\- -f1`
@@ -86,19 +84,8 @@ short=$(echo "${jvmver}" | cut -c1-2)
 
 JAVA_VERSION=22
 
-if [ "$JVM_VERSION" = "1.8.0" ]  ; then
-    JVM_PATCH_VERSION=${jvmver#*_}
-    if [ "$JVM_VERSION" \< "1.8" ] || [ "$JVM_VERSION" \> "1.8.2" ] ; then
-        echo "Cassandra 4.0 requires either Java 8 (update 151 or newer) or Java 11 (or newer). Java $JVM_VERSION is not supported."
-        exit 1;
-    fi
-    if [ "$JVM_PATCH_VERSION" -lt 151 ] ; then
-        echo "Cassandra 4.0 requires either Java 8 (update 151 or newer) or Java 11 (or newer). Java 8 update $JVM_PATCH_VERSION is not supported."
-        exit 1;
-    fi
-    JAVA_VERSION=8
-elif [ "$JVM_VERSION" \< "11" ] ; then
-    echo "Cassandra 4.0 requires either Java 8 (update 151 or newer) or Java 11 (or newer)."
+if [ "$JVM_VERSION" \< "11" ] ; then
+    echo "Cassandra 4.0 requires either Java 11 or newer."
     exit 1;
 elif [ "$short" = "11" ] ; then
      JAVA_VERSION=11