fix(rbac): updated a word translation in Ja

[ciiay]

Hey, I just made a Pull Request!

Before the fix:
Overview => 概要
About => 概要

After the fix:
Overview => 概要
About => 詳細情報

✔️ Checklist

• A changeset describing the change and affected packages. (more info)
• Added or updated documentation
• Tests for new functionality and regression tests for bug fixes
• Screenshots attached (for UI changes)
• All your commits have a Signed-off-by line in the message. (more info)

[backstage-goalie]

Missing Changesets

The following package(s) are changed by this PR but do not have a changeset:

• @backstage-community/plugin-rbac

See CONTRIBUTING.md for more information about how to add changesets.

Changed Packages

Package Name	Package Path	Changeset Bump	Current Version
@backstage-community/plugin-rbac	workspaces/rbac/plugins/rbac	none	v1.48.0