Bump versions after 8.8.0 release

.ci/bwcVersions

@@ -87,6 +87,6 @@ BWC_VERSION:
   - "8.6.2"
   - "8.7.0"
   - "8.7.1"
-  - "8.7.2"
   - "8.8.0"
+  - "8.8.1"
   - "8.9.0"

.ci/snapshotBwcVersions

@@ -1,5 +1,4 @@
 BWC_VERSION:
   - "7.17.11"
-  - "8.7.2"
-  - "8.8.0"
+  - "8.8.1"
   - "8.9.0"

server/src/main/java/org/elasticsearch/Version.java

@@ -138,8 +138,8 @@ public class Version implements Comparable<Version>, ToXContentFragment {
     public static final Version V_8_6_2 = new Version(8_06_02_99, org.apache.lucene.util.Version.LUCENE_9_4_2);
     public static final Version V_8_7_0 = new Version(8_07_00_99, org.apache.lucene.util.Version.LUCENE_9_5_0);
     public static final Version V_8_7_1 = new Version(8_07_01_99, org.apache.lucene.util.Version.LUCENE_9_5_0);
-    public static final Version V_8_7_2 = new Version(8_07_02_99, org.apache.lucene.util.Version.LUCENE_9_5_0);
     public static final Version V_8_8_0 = new Version(8_08_00_99, org.apache.lucene.util.Version.LUCENE_9_6_0);
+    public static final Version V_8_8_1 = new Version(8_08_01_99, org.apache.lucene.util.Version.LUCENE_9_6_0);
     public static final Version V_8_9_0 = new Version(8_09_00_99, org.apache.lucene.util.Version.LUCENE_9_6_0);
     public static final Version CURRENT = V_8_9_0;