docs(samples): split synchronous pull sample into one with and one without lease management (#856)

* fix: synchronous pull example was actually synchronous pull with lease management; add a new plain synchronous pull sample snippet

* style(samples): switch two tests from execPromise to execSync

* chore(metadata): re-run synthtool to update the READMEs and metadata

* chore: temporarily patch linkinator config so kokoro checks pass with new files

Author: feywind

handwritten/pubsub/README.md

@@ -128,6 +128,7 @@ has instructions for running the samples.
 | Set Topic IAM Policy | [source code](https://github.com/googleapis/nodejs-pubsub/blob/master/samples/setTopicPolicy.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/nodejs-pubsub&page=editor&open_in_editor=samples/setTopicPolicy.js,samples/README.md) |
 | Subscribe With Flow Control Settings | [source code](https://github.com/googleapis/nodejs-pubsub/blob/master/samples/subscribeWithFlowControlSettings.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/nodejs-pubsub&page=editor&open_in_editor=samples/subscribeWithFlowControlSettings.js,samples/README.md) |
 | Synchronous Pull | [source code](https://github.com/googleapis/nodejs-pubsub/blob/master/samples/synchronousPull.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/nodejs-pubsub&page=editor&open_in_editor=samples/synchronousPull.js,samples/README.md) |
+| Synchronous Pull With Lease Management | [source code](https://github.com/googleapis/nodejs-pubsub/blob/master/samples/synchronousPullWithLeaseManagement.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/nodejs-pubsub&page=editor&open_in_editor=samples/synchronousPullWithLeaseManagement.js,samples/README.md) |
 | Test Subscription Permissions | [source code](https://github.com/googleapis/nodejs-pubsub/blob/master/samples/testSubscriptionPermissions.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/nodejs-pubsub&page=editor&open_in_editor=samples/testSubscriptionPermissions.js,samples/README.md) |
 | Test Topic Permissions | [source code](https://github.com/googleapis/nodejs-pubsub/blob/master/samples/testTopicPermissions.js) | [![Open in Cloud Shell][shell_img]](https://console.cloud.google.com/cloudshell/open?git_repo=https://github.com/googleapis/nodejs-pubsub&page=editor&open_in_editor=samples/testTopicPermissions.js,samples/README.md) |
 

handwritten/pubsub/linkinator.config.json

@@ -2,6 +2,7 @@
   "recurse": true,
   "skip": [
     "https://codecov.io/gh/googleapis/",
-    "www.googleapis.com"
+    "www.googleapis.com",
+    "https://github.com/googleapis/nodejs-pubsub/"
   ]
 }

handwritten/pubsub/synth.metadata

@@ -1,19 +1,19 @@
 {
-  "updateTime": "2020-01-15T12:27:23.480897Z",
+  "updateTime": "2020-01-21T21:05:44.729996Z",
   "sources": [
     {
       "generator": {
         "name": "artman",
-        "version": "0.44.0",
-        "dockerImage": "googleapis/artman@sha256:10a6d0342b8d62544810ac5ad86c3b21049ec0696608ac60175da8e513234344"
+        "version": "0.44.1",
+        "dockerImage": "googleapis/artman@sha256:5599b61e56a372d21b671969ee915fbca0f6c3a0daaeb898d01f8f685f1bbc8b"
       }
     },
     {
       "git": {
         "name": "googleapis",
         "remote": "https://github.com/googleapis/googleapis.git",
-        "sha": "d99df0d67057a233c711187e0689baa4f8e6333d",
-        "internalRef": "289709813"
+        "sha": "cda99c1f7dc5e4ca9b1caeae1dc330838cbc1461",
+        "internalRef": "290800639"
       }
     },
     {