web-bundles: Update Go CLI tool install command

The previous command to install the CLI was outdated.

Bug: None
Change-Id: I0f7be9a2d4defdc01858eb5aff9e7d9b803cb734
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4055472
Commit-Queue: Christian Flach <cmfcmf@chromium.org>
Reviewed-by: Sonja Laurila <laurila@google.com>
Cr-Commit-Position: refs/heads/main@{#1076093}

web-bundle/README.md

@@ -5,6 +5,6 @@ This directory contains tests for the
 [webpackage repository](https://github.com/WICG/webpackage).
 To install them, run:
 ```
-go get -u github.com/WICG/webpackage/go/bundle/cmd/...
+go install github.com/WICG/webpackage/go/bundle/cmd/...@latest
 export PATH=$PATH:$(go env GOPATH)/bin
 ```

web-bundle/resources/generate-test-wbns.sh

@@ -4,7 +4,7 @@ set -e
 
 if ! command -v gen-bundle > /dev/null 2>&1; then
     echo "gen-bundle is not installed. Please run:"
-    echo "  go get -u github.com/WICG/webpackage/go/bundle/cmd/..."
+    echo "  go install github.com/WICG/webpackage/go/bundle/cmd/...@latest"
     echo '  export PATH=$PATH:$(go env GOPATH)/bin'
     exit 1
 fi