chore(main): release 0.123.19-SNAPSHOT (#729)

🤖 I have created a release *beep* *boop*
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### Updating meta-information for bleeding-edge SNAPSHOT release.

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This PR was generated with [Release Please](https://togithub.com/googleapis/release-please). See [documentation](https://togithub.com/googleapis/release-please#release-please).

java-notification/pom.xml

@@ -4,7 +4,7 @@
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <artifactId>google-cloud-notification</artifactId>
-  <version>0.123.18-beta</version><!-- {x-version-update:google-cloud-notification:current} -->
+  <version>0.123.19-beta-SNAPSHOT</version><!-- {x-version-update:google-cloud-notification:current} -->
   <packaging>jar</packaging>
   <name>Google Cloud Pub/Sub Notifications for GCS</name>
   <url>https://github.com/googleapis/java-notification</url>

java-notification/samples/snapshot/pom.xml

@@ -28,7 +28,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-notification</artifactId>
-      <version>0.123.18-beta</version>
+      <version>0.123.19-beta-SNAPSHOT</version>
     </dependency>
     <!-- {x-version-update-end} -->
 

java-notification/versions.txt

@@ -1,4 +1,4 @@
 # Format:
 # module:released-version:current-version
 
-google-cloud-notification:0.123.18-beta:0.123.18-beta
+google-cloud-notification:0.123.18-beta:0.123.19-beta-SNAPSHOT