Fix settings to build with newer Java version

[KodaiD]

Description

In PR 211, it was reported that some samples could not be built with newer Java versions. In this PR, I modify some build.gradle files to build all ScalarDB samples with Java 8, 11, 17.

Related issues and/or PRs

• https://github.com/scalar-labs/docs-internal-scalardb/pull/211

Changes made

• I remove spotlessJava task because an error occurs at the removeUnusedImports() in spotlessJava task (This error is reported by an issue in google-java-format) and the task is only used in two samples. This decision was approved by @brfrn169.
• I add java.annotation dependency explicitly because javax.annotation.Generated used in one sample is not included in Java 9 and later (ref. Replace javax.annotation.Generated with custom gRPC annotation grpc/grpc-java#9179).

Checklist

• I have commented my code, particularly in hard-to-understand areas.
• I have updated the documentation to reflect the changes.
• Any remaining open issues linked to this PR are documented and up-to-date (Jira, GitHub, etc.).
• Tests (unit, integration, etc.) have been added for the changes.
• My changes generate no new warnings.
• Any dependent changes in other PRs have been merged and published.

[kota2and3kan]

LGTM! Thank you!

FYI: I was able to build these three updated samples by using Java 17 in my local environment!

[Torch3333]

LGTM, thank you!

[brfrn169]

LGTM! Thank you!

@KodaiD Do the other samples work with the newer Java versions? Or do we need to do something for them as well?

[KodaiD]

LGTM! Thank you!

@KodaiD Do the other samples work with the newer Java versions? Or do we need to do something for them as well?

@brfrn169 Thanks for reviewing this.
I've confirmed that all samples (except scalardb-analytics-postgresql-sample, scalardb-analytics-spark-sample, scalardb-cluster-standalone-mode, scalardb-kotlin-sample) can be built with Java 8, 11, 17.

[feeblefakie]

LGTM! Thank you!