bump helm-tiller addon to v2.16.8

[govargo]

What type of PR is this?

/area addons

What this PR does / why we need it:

This PR bump up helm-tiller addon's image v2.16.7 to v2.16.8.
This fix high-severity security vulnerability in helm2(tiller) addons.

Which issue(s) this PR fixes:

Fixes #8470

Does this PR introduce a user-facing change?

Yes.
This image bumpup includes helm2 security patch.
https://github.com/helm/helm/releases/tag/v2.16.8

Before

image: gcr.io/kubernetes-helm/tiller:v2.16.7

After

image: gcr.io/kubernetes-helm/tiller:v2.16.8

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

NONE

[k8s-ci-robot]

Hi @govargo. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: govargo
To complete the pull request process, please assign priyawadhwa
You can assign the PR to them by writing /assign @priyawadhwa in a comment when ready.

The full list of commands accepted by this bot can be found here.

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[govargo]

/assign @priyawadhwa

[TravisBuddy]

Travis tests have failed

Hey @govargo,
Please read the following log in order to understand the failure reason.
It'll be awesome if you fix what's wrong and commit the changes.

1st Build

View build log

make test

which go-bindata || GO111MODULE=off GOBIN="/home/travis/gopath/bin" go get github.com/jteeuwen/go-bindata/...
PATH="/home/travis/gopath/bin:/home/travis/.gimme/versions/go1.13.8.linux.amd64/bin:/home/travis/bin:/home/travis/bin:/home/travis/.local/bin:/usr/local/lib/jvm/openjdk11/bin:/opt/pyenv/shims:/home/travis/.phpenv/shims:/home/travis/perl5/perlbrew/bin:/home/travis/.nvm/versions/node/v8.12.0/bin:/home/travis/.rvm/gems/ruby-2.5.3/bin:/home/travis/.rvm/gems/ruby-2.5.3@global/bin:/home/travis/.rvm/rubies/ruby-2.5.3/bin:/home/travis/gopath/bin:/home/travis/.gimme/versions/go1.11.1.linux.amd64/bin:/usr/local/maven-3.6.0/bin:/usr/local/cmake-3.12.4/bin:/usr/local/clang-7.0.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/home/travis/.rvm/bin:/home/travis/.phpenv/bin:/opt/pyenv/bin:/home/travis/.yarn/bin:/home/travis/gopath/bin" go-bindata -nomemcopy -o pkg/minikube/assets/assets.go -pkg assets deploy/addons/...
gofmt -s -w pkg/minikube/assets/assets.go
which go-bindata || GO111MODULE=off GOBIN="/home/travis/gopath/bin" go get github.com/jteeuwen/go-bindata/...
/home/travis/gopath/bin/go-bindata
PATH="/home/travis/gopath/bin:/home/travis/.gimme/versions/go1.13.8.linux.amd64/bin:/home/travis/bin:/home/travis/bin:/home/travis/.local/bin:/usr/local/lib/jvm/openjdk11/bin:/opt/pyenv/shims:/home/travis/.phpenv/shims:/home/travis/perl5/perlbrew/bin:/home/travis/.nvm/versions/node/v8.12.0/bin:/home/travis/.rvm/gems/ruby-2.5.3/bin:/home/travis/.rvm/gems/ruby-2.5.3@global/bin:/home/travis/.rvm/rubies/ruby-2.5.3/bin:/home/travis/gopath/bin:/home/travis/.gimme/versions/go1.11.1.linux.amd64/bin:/usr/local/maven-3.6.0/bin:/usr/local/cmake-3.12.4/bin:/usr/local/clang-7.0.0/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/home/travis/.rvm/bin:/home/travis/.phpenv/bin:/opt/pyenv/bin:/home/travis/.yarn/bin:/home/travis/gopath/bin" go-bindata -nomemcopy -o pkg/minikube/translate/translations.go -pkg translate translations/...
gofmt -s -w pkg/minikube/translate/translations.go
MINIKUBE_LDFLAGS="-X k8s.io/minikube/pkg/version.version=v1.11.0 -X k8s.io/minikube/pkg/version.isoVersion=v1.11.0 -X k8s.io/minikube/pkg/version.isoPath=minikube/iso -X k8s.io/minikube/pkg/version.gitCommitID="4d2a2417799f00a283a583b82e928a61fb37eb89"" ./test.sh
= make lint =============================================================
golangci/golangci-lint info checking GitHub for tag 'v1.26.0'
golangci/golangci-lint crit unable to find 'v1.26.0' - use 'latest' or see https://github.com/golangci/golangci-lint/releases for details
Makefile:371: recipe for target 'out/linters/golangci-lint-v1.26.0' failed
make[1]: *** [out/linters/golangci-lint-v1.26.0] Error 1
= go mod ================================================================
ok
= boilerplate ===========================================================
ok
Makefile:273: recipe for target 'test' failed
make: *** [test] Error 4

TravisBuddy Request Identifier: 956b1090-ad42-11ea-8b2d-cffda33d3704

[minikube-bot]

Can one of the admins verify this patch?