Update asciidoctor-plantuml 0.0.9 -> 0.0.10

What does this MR do?

Update asciidoctor-plantuml from 0.0.9 to 0.0.10

It changes asciidoctor-plantuml/plantuml.rb to asciidoctor_plantuml/plantuml.rb though not sure if we can just require 'asciidoctor-plantuml' instead of requiring a specific file (we already depend on asciidoctor so it does not add any extra dependencies).

Full changes https://github.com/hsanson/asciidoctor-plantuml/compare/v0.0.9...v0.0.10

Debian already have 0.0.10 so keeping this in sync helps packaging.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team