Fix RandomData generating bad values

Author: AuroraLS3

Plan/common/src/main/java/com/djrapitops/plan/gathering/domain/FinishedSession.java

@@ -187,7 +187,7 @@ public boolean equals(Object o) {
      * @return Serialized format
      */
     public String serializeCSV() {
-        return String.valueOf(playerUUID) + ';' +
+        return (String.valueOf(playerUUID) + ';' +
                 serverUUID + ';' +
                 start + ';' +
                 end + ';' +
@@ -200,7 +200,8 @@ public String serializeCSV() {
                 getExtraData(JoinAddress.class).map(JoinAddress::getAddress)
                         .map(address -> address.replace(';', ':'))
                         .orElse(JoinAddressTable.DEFAULT_VALUE_FOR_LOOKUP) + ';' +
-                getExtraData(PlayerName.class).map(PlayerName::get).orElseGet(playerUUID::toString);
+                getExtraData(PlayerName.class).map(PlayerName::get).orElseGet(playerUUID::toString))
+                .replace('\\', '_'); // Untrusted data can contain escape characters that fail json serialization.
     }
 
     public static class Id {

Plan/common/src/testFixtures/java/utilities/RandomData.java

@@ -61,7 +61,9 @@ public static long randomLong(long rangeStart, long rangeEnd) {
 
     public static String randomString(int size) {
         return new RandomStringGenerator.Builder().withinRange('A', 'z').get()
-                .generate(size);
+                .generate(size)
+                .replace(';', '_')
+                .replace('\\', '_');
     }
 
     public static List<Nickname> randomNicknames(ServerUUID serverUUID) {