Bump mssql-jdbc in /modules/mssqlserver

Bumps [mssql-jdbc](https://github.com/Microsoft/mssql-jdbc) from 11.2.1.jre8 to 12.1.0.jre8-preview.
- [Release notes](https://github.com/Microsoft/mssql-jdbc/releases)
- [Changelog](https://github.com/microsoft/mssql-jdbc/blob/main/CHANGELOG.md)
- [Commits](https://github.com/Microsoft/mssql-jdbc/commits)

---
updated-dependencies:
- dependency-name: com.microsoft.sqlserver:mssql-jdbc
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

modules/mssqlserver/build.gradle

@@ -10,7 +10,7 @@ dependencies {
     compileOnly 'io.r2dbc:r2dbc-mssql:0.9.0.RELEASE'
 
     testImplementation project(':jdbc-test')
-    testImplementation 'com.microsoft.sqlserver:mssql-jdbc:11.2.1.jre8'
+    testImplementation 'com.microsoft.sqlserver:mssql-jdbc:12.1.0.jre8-preview'
 
     testImplementation project(':r2dbc')
     testImplementation 'io.r2dbc:r2dbc-mssql:0.8.7.RELEASE'