docs(spanner): snippets to set transaction options#2194

skuruppu wants to merge 1 commit intoGoogleCloudPlatform:mainGoogleCloudPlatform/php-docs-samples:mainfrom

skuruppu:spanner-read-lock-mode-samplesskuruppu/php-docs-samples:spanner-read-lock-mode-samplesCopy head branch name to clipboard