feat: add log4j2 configuration

[OrezzerO]

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• Why submit this pull request?

• [ ] Bugfix

• [x] New feature provided

• [ ] Improve performance

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New feature or improvement

• Describe the details and related test reports. Add log4j configuration. The logs will be at ${user.dir}/logs/java-runner-common-default.log and ${user.dir}/logs/java-runner-common-error.log. In apisix env, ${user.dir} generally equals /usr/local/apisix/.

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Related issue: #22

[tzssangglass]

we need to add log path to https://github.com/apache/apisix-java-plugin-runner/blob/main/.gitignore#L25

[tzssangglass]

@OrezzerO merged, many thanks.