docs: Update plugin pwa docs

[kefranabg]

Summary

Fix plugin pwa docs example

What kind of change does this PR introduce? (check at least one)

• Bugfix
• Feature
• Code style update
• Refactor
• Docs
• Build-related changes
• Other, please describe:

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Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

The PR fulfills these requirements:

• When resolving a specific issue, it's referenced in the PR's title (e.g. fix #xxx[,#xxx], where "xxx" is the issue number)

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If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature
• Related documents have been updated
• Related tests have been updated

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