docs(owlbot-java): explaining why not using formatter in pom.xml (#1511) (#945)

Fixes #1502
Source-Link: googleapis/synthtool@26ea255
Post-Processor: gcr.io/cloud-devrel-public-resources/owlbot-java:latest@sha256:7a9a7eb50ca2af5bfffab3abd2f38d408735c990a74bacf9b7fde2af0a086a0b

Author: gcf-owl-bot[bot]

.github/.OwlBot.lock.yaml

@@ -13,5 +13,5 @@
 # limitations under the License.
 docker:
   image: gcr.io/cloud-devrel-public-resources/owlbot-java:latest
-  digest: sha256:b2e8f445ca0e605d4bbefbfdbdf7335692d75cf1647af62243828dcc0ea4e690
-# created: 2022-07-14T21:08:10.768472192Z
+  digest: sha256:7a9a7eb50ca2af5bfffab3abd2f38d408735c990a74bacf9b7fde2af0a086a0b
+# created: 2022-08-01T15:27:14.757266067Z