📦 Update dependency rollup to v2.39.0

[renovate-bot]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
rollup (source)	2.38.5 -> 2.39.0

How to resolve breaking changes

This PR may introduce breaking changes that require manual intervention. In such cases, you will need to check out this branch, fix the cause of the breakage, and commit the fix to ensure a green CI build. To check out and update this PR, follow the steps below:

# Check out the PR branch (these steps are from GitHub)
git checkout -b renovate-bot-renovate/subpackage-devdependencies master
git pull https://github.com/renovate-bot/amphtml.git renovate/subpackage-devdependencies

# Directly make fixes and commit them
gulp lint --fix # For lint errors in JS files
gulp prettify --fix # For prettier errors in non-JS files
# Edit source code in case of new compiler warnings / errors

# Push the changes to the branch
git push git@github.com:renovate-bot/amphtml.git renovate-bot-renovate/subpackage-devdependencies:renovate/subpackage-devdependencies

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Release Notes

rollup/rollup

v2.39.0

Compare Source

2021-02-12

Features

• Add "validate" option to verify generated chunks are valid JavaScript (#​3952)

Bug Fixes

• Always add exports properties for uninitialized named exports (#​3957)
• Allow using an external namespace reexport together with named exports (#​3959)
• Avoid invalid generated code in certain scenarios with SystemJS exports (#​3960)

Pull Requests

• #​3952: implement validate output option and --validate CLI option (@​kzc)
• #​3956: Update dependencies, fix fsevents issue (@​lukastaegert)
• #​3957: Make sure uninitialised exports turn up via .hasOwnProperty for non-ES formats (@​lukastaegert)
• #​3959: Allow overriding individual exports of reexported external namespaces (@​lukastaegert)
• #​3960: Make sure system exports are valid JavaScript
  (@​lukastaegert)

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