chore: switch master branch to use v1.7.0

[andyzhangx]

What type of PR is this?
/kind documentation

What this PR does / why we need it:
chore: switch master branch to use v1.7.0

Which issue(s) this PR fixes:

Fixes #

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Special notes for your reviewer:

git checkout -b switch-master-1.7.0
sed -i 's/1.6.0/1.7.0/g' Makefile
cd charts/latest/
sed -i 's/1.6.0/1.7.0/g' azuredisk-csi-driver/Chart.yaml
helm package azuredisk-csi-driver
git rm azuredisk-csi-driver-v1.6.0.tgz
git add azuredisk-csi-driver-v1.7.0.tgz
cd ../../
helm repo index charts --url=https://raw.githubusercontent.com/kubernetes-sigs/azuredisk-csi-driver/master/charts
$git_commit
git push origin switch-master-1.7.0

Release note:

none

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: andyzhangx

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• OWNERS [andyzhangx]

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