Roll back dependency @polymer/iron-component-page to v1.0.0-art-external1

[lne-bamboo]

This PR contains the following updates:

Package	Type	Update	Change
@polymer/iron-component-page	dependencies	rollback	4.0.1 -> 1.0.0-art-external1
@polymer/iron-component-page	devDependencies	rollback	^3.0.0-pre.12 -> ^1.0.0-art-external1

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Configuration

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This PR has been generated by Renovate Bot.

[lne-bamboo]

⚠ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
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The artifact failure details are included below:

File name: package-lock.json

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