chore: release 1.18.3 (#310)

🤖 I have created a release \*beep\* \*boop\* 
---
### [1.18.3](https://www.github.com/googleapis/java-spanner-jdbc/compare/v1.18.2...v1.18.3) (2020-12-16)


### Dependencies

* update spanner to 3.1.2 ([#306](https://www.github.com/googleapis/java-spanner-jdbc/issues/306)) ([596e8ed](https://www.github.com/googleapis/java-spanner-jdbc/commit/596e8ed01dc8ffc01c37b233f688d163b8693f85))
---


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

Author: release-please[bot]

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+### [1.18.3](https://www.github.com/googleapis/java-spanner-jdbc/compare/v1.18.2...v1.18.3) (2020-12-16)
+
+
+### Dependencies
+
+* update spanner to 3.1.2 ([#306](https://www.github.com/googleapis/java-spanner-jdbc/issues/306)) ([596e8ed](https://www.github.com/googleapis/java-spanner-jdbc/commit/596e8ed01dc8ffc01c37b233f688d163b8693f85))
+
 ### [1.18.2](https://www.github.com/googleapis/java-spanner-jdbc/compare/v1.18.1...v1.18.2) (2020-12-16)
 
 

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-spanner-jdbc</artifactId>
-  <version>1.18.3-SNAPSHOT</version><!-- {x-version-update:google-cloud-spanner-jdbc:current} -->
+  <version>1.18.3</version><!-- {x-version-update:google-cloud-spanner-jdbc:current} -->
   <packaging>jar</packaging>
   <name>Google Cloud Spanner JDBC</name>
   <url>https://github.com/googleapis/java-spanner-jdbc</url>

samples/snapshot/pom.xml

@@ -28,7 +28,7 @@
     <dependency>
       <groupId>com.google.cloud</groupId>
       <artifactId>google-cloud-spanner-jdbc</artifactId>
-      <version>1.18.3-SNAPSHOT</version>
+      <version>1.18.3</version>
     </dependency>
     <!-- {x-version-update-end} -->
 

versions.txt

@@ -1,4 +1,4 @@
 # Format:
 # module:released-version:current-version
 
-google-cloud-spanner-jdbc:1.18.2:1.18.3-SNAPSHOT
+google-cloud-spanner-jdbc:1.18.3:1.18.3