chore: upgrade all dependencies

[wardpeet]

I've revisited the upgrade dependencies PR. This one has less changes and it's easier to follow.

Updated majors:

package	old	new	changelog
rollup	1.32.1	2.29.0	http://github.com/rollup/rollup/releases/tag/v2.0.0
@rollup/plugin-commonjs	13.0.0	15.1.0	https://github.com/rollup/plugins/blob/master/packages/commonjs/CHANGELOG.md#v1400 https://github.com/rollup/plugins/blob/master/packages/commonjs/CHANGELOG.md#v1500
@rollup/plugin-node-resolve	6.1.0	9.0.0	https://github.com/rollup/plugins/blob/master/packages/node-resolve/CHANGELOG.md#v700 https://github.com/rollup/plugins/blob/master/packages/node-resolve/CHANGELOG.md#v800 https://github.com/rollup/plugins/blob/master/packages/node-resolve/CHANGELOG.md#v900
camelcase	5.3.1	6.1.0	https://github.com/sindresorhus/camelcase/releases/tag/v6.0.0
kleur	3.0.3	4.1.3	https://github.com/lukeed/kleur/tree/v4.0.0
rollup-plugin-postcss	2.9.0	3.1.8	https://github.com/egoist/rollup-plugin-postcss/releases/tag/v3.0.0
rollup-plugin-terser	5.3.1	7.0.2	https://github.com/TrySound/rollup-plugin-terser/tree/v6.0.0 https://github.com/TrySound/rollup-plugin-terser/tree/v7.0.0
rollup-plugin-typescript2	0.25.3	0.27.3	https://github.com/ezolenko/rollup-plugin-typescript2/tree/0.26.0 https://github.com/ezolenko/rollup-plugin-typescript2/tree/0.27.0
tslib	1.13.0	2.0.3	https://github.com/microsoft/tslib/releases/tag/2.0.0
typescript	3.9.5	4.0.3	https://devblogs.microsoft.com/typescript/announcing-typescript-4-0/

Changes in tests:

• the gluecode for umd wrappers do now have globalThis which makes it a little bit bigger
• by using compress of the postcss-plugin we have less css (newlines got removed)
• the upgraded postcss-plugin fixes a few bugs we have where we minimized classnames when it was false
• Terser seems to make a few builds bigger

[changeset-bot]

🦋 Changeset detected

Latest commit: 9d2e35f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
microbundle	Minor

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[katywings]

@wardpeet Since this upgrades rollup to a new major version, isnt it likely that it will break microbundle for some users 🤔. @developit Would it make sense to prerelease this in some form, so that users first can test it?

[Parader]

Would use this update in my library as soon as it is available 👍
+1