docs: fix typo in design guidelines

[weensy]

Issue # (if applicable)

Closes #38119.

Reason for this change

The design guidelines contained a typo in the word "inheritance".

Description of changes

Corrected inheritence to inheritance in docs/DESIGN_GUIDELINES.md.

Describe any new or updated permissions being added

N/A. This is a documentation-only change.

Description of how you validated changes

Not run; docs-only typo fix.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[weensy]

🤖 Agent Docs Sync Reminder

This PR modifies human-facing documentation that has corresponding agent-facing docs. Please check whether the following agent-facing files need matching updates:

• AGENTS.md
• docs/AGENTS_CONSTRUCT_DESIGN.md
• docs/AGENTS_CONSTRUCT_IMPLEMENTATION.md

If you consider no agent-facing changes are needed, leave a comment explaining why and a maintainer will remove the agent-docs-review-needed label.

I checked the agent-facing docs listed in the reminder:

• AGENTS.md
• docs/AGENTS_CONSTRUCT_DESIGN.md
• docs/AGENTS_CONSTRUCT_IMPLEMENTATION.md

No matching update is needed for this PR. The change only corrects a typo in an awslint rule reference in docs/DESIGN_GUIDELINES.md (construct-inheritence -> construct-inheritance). The agent-facing docs do not contain this rule reference, and the corresponding guidance in docs/AGENTS_CONSTRUCT_DESIGN.md already uses the correctly spelled word "inheritance"

[github-actions]

🤖 Agent Docs Sync Reminder

This PR modifies human-facing documentation that has corresponding agent-facing docs.
Please check whether the following agent-facing files need matching updates:

• AGENTS.md
• docs/AGENTS_CONSTRUCT_DESIGN.md
• docs/AGENTS_CONSTRUCT_IMPLEMENTATION.md

If you consider no agent-facing changes are needed, leave a comment explaining why
and a maintainer will remove the agent-docs-review-needed label.

[matboros]

Duplicate of #38150

[github-actions]

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