📖 Correct Helm chart install instructions in docs + add warnings about --wait being required

[willie-yao]

What this PR does / why we need it:
This PR adds some fixes to the helm chart install commands in the docs. It also adds some warnings regarding the --wait flag being required when installing providers with the helm chart.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #532

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[alexander-demicev]

Thanks for taking care of it

@Fedosin @furkatgofurov7 @Danil-Grigorev ptal

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: alexander-demicev

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• OWNERS [alexander-demicev]

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[Danil-Grigorev]

The docs improvements are always good. Thank you @willie-yao
/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 23288f303dcf1e80a6451341d70fef4a4ed1c87d

[furkatgofurov7]

Thanks @willie-yao!

/lgtm

[furkatgofurov7]

/cherry-pick release-0.11

[k8s-infra-cherrypick-robot]

@furkatgofurov7: once the present PR merges, I will cherry-pick it on top of release-0.11 in a new PR and assign it to you.

In response to this:

/cherry-pick release-0.11

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[k8s-infra-cherrypick-robot]

@furkatgofurov7: new pull request created: #552

In response to this:

/cherry-pick release-0.11

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.