feat!: BREAKING CHANGE: Support webpack@5 typings

[SunHuawei]

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

If yes, then include "BREAKING CHANGES:" in the first commit message body, followed by a description of what is breaking.

List any relevant issue numbers:
#279

Description

As you've known that webpack@5 is having a totally different typing definition, and there is no way to support v4 and v5 at the same time. So one choice is just to release a major version to only support webpack 5.

[SunHuawei]

@shellscape , there are 3 workflows awaiting approval, would you please help with this?

[nigelellis]

We're hitting this in a recent version bump. Anything I can do to help get this PR merged?

[SunHuawei]

I'm still waiting for the owner to approve the workflow.
@nigel-codaio, here is the npm package published from my forked repo. You can use npm i webpack-manifest-plugin-v5 for a temporary solution.