Update README.md

Author: gautamdsheth

docker/README.md

@@ -17,7 +17,7 @@ $securedPassword = ConvertTo-SecureString $DOCKER_PASSWORD -AsPlainText -Force
 
 ```powershell
 $securedPassword = ConvertTo-SecureString $DOCKER_PASSWORD -AsPlainText -Force
-./docker/Publish-UnpublishedImage.ps1 PnP.PowerShell $DOCKER_USERNAME $DOCKER_ORG powershell $securedPassword $false "root" "alpine-3.14"
+./docker/Publish-UnpublishedImage.ps1 PnP.PowerShell $DOCKER_USERNAME $DOCKER_ORG powershell $securedPassword $false "root" "alpine-3.16.5"
 ```
 
 # Publish with prereleases manually in Windows
@@ -52,10 +52,10 @@ docker push "$DOCKER_ORG/powershell:$VERSION-nanoserver-1809"
 
 ```bash
 VERSION=$(cat ./version.txt)-nightly
-docker build --build-arg "PNP_MODULE_VERSION=$VERSION" --build-arg "BASE_IMAGE_SUFFIX=alpine-3.14" --build-arg "INSTALL_USER=root" --build-arg "SKIP_PUBLISHER_CHECK=False" ./docker -f ./docker/pnppowershell.dockerFile --tag $DOCKER_ORG/powershell:$VERSION-alpine-3.14;
-docker image tag $DOCKER_ORG/powershell:$VERSION-alpine-3.14 $DOCKER_ORG/powershell:nightly
+docker build --build-arg "PNP_MODULE_VERSION=$VERSION" --build-arg "BASE_IMAGE_SUFFIX=alpine-3.16.5" --build-arg "INSTALL_USER=root" --build-arg "SKIP_PUBLISHER_CHECK=False" ./docker -f ./docker/pnppowershell.dockerFile --tag $DOCKER_ORG/powershell:$VERSION-alpine-3.16.5;
+docker image tag $DOCKER_ORG/powershell:$VERSION-alpine-3.16.5 $DOCKER_ORG/powershell:nightly
 docker login -u $DOCKER_USERNAME -p "$DOCKER_PASSWORD"
-docker push $DOCKER_ORG/powershell:$VERSION-alpine-3.14
+docker push $DOCKER_ORG/powershell:$VERSION-alpine-3.16.5
 docker push $DOCKER_ORG/powershell:nightly
 ```