Update system event variants

[ECJ222]

This is a Companion PR to paritytech/substrate#10296

skip check-dependent-cumulus

[ECJ222]

please could you review this pr @athei and @kianenigma.

[ECJ222]

Hi @athei, The CI keeps failing, please is there a way I can fix this?

[athei]

The companion CI will always fail because it builds against the current substrate master which does not include your changes. Don't look at it.

You need to concentrate on making your substrate PR's CI green. The continuous-integration/gitlab-check-dependent-polkadot job there builds the polkadot companion against your PR. This is the one failing. This means that your companion (this PR) has build failures. So fix them and your substrate PR will get green. I can trigger the CI there once you made the changes here.

[ECJ222]

Thank you @athei, I made a few changes to the initial pr I sent.

[bkchr]

bot merge

[paritytech-processbot]

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{"documentation_url":"https://docs.github.com/rest/reference/pulls#get-a-pull-request","message":"Not Found"}