Add patch for insecure proxy support for helm

[ahreehong]

Issue #, if available:

Description of changes:
We removed our patches adding support for the flag --insecure-skip-tls-verify, as the functionality had been added to upstream helm. However, upstream has a bug when using proxy with the --insecure-skip-tls-verify flag so the helm commands fails.

This PR adds a patch to fix this bug

Testing
Manually ran helm commands with the --insecure-skip-tls-verify flag with proxy and verified the commands work.
Built EKS-A controller to use the patched helm and verified cluster creation worked.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[ahreehong]

/approve

[eks-distro-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ahreehong

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[ahreehong]

/cherry-pick release-0.19

[eks-distro-pr-bot]

@ahreehong: #3046 failed to apply on top of branch "release-0.19":

Applying: Add patch for insecure proxy support for helm
.git/rebase-apply/patch:41: space before tab in indent.
 			IdleConnTimeout:       90 * time.Second,
.git/rebase-apply/patch:42: space before tab in indent.
 			TLSHandshakeTimeout:   10 * time.Second,
.git/rebase-apply/patch:43: space before tab in indent.
 			ExpectContinueTimeout: 1 * time.Second,
.git/rebase-apply/patch:45: space before tab in indent.
 		}
.git/rebase-apply/patch:46: space before tab in indent.
 	})
warning: squelched 11 whitespace errors
warning: 16 lines add whitespace errors.
Using index info to reconstruct a base tree...
M	projects/helm/helm/CHECKSUMS
Falling back to patching base and 3-way merge...
Auto-merging projects/helm/helm/CHECKSUMS
CONFLICT (content): Merge conflict in projects/helm/helm/CHECKSUMS
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 Add patch for insecure proxy support for helm
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

In response to this:

/cherry-pick release-0.19

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