samples: add presubmit lint check (#197)

This PR was generated using Autosynth. 🌈

Synth log will be available here:
https://source.cloud.google.com/results/invocations/04a3c534-5129-4a05-922f-148232720a95/targets

- [ ] To automatically regenerate this PR, check this box.

Source-Link: googleapis/synthtool@9602086
Source-Link: googleapis/synthtool@c3caf07

.github/workflows/samples.yaml

@@ -0,0 +1,14 @@
+on:
+  pull_request:
+name: samples
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-java@v1
+        with:
+          java-version: 8
+      - name: Run checkstyle
+        run: mvn -P lint --quiet --batch-mode checkstyle:check
+        working-directory: samples/snippets

synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-storage-nio.git",
-        "sha": "9bbc1fc755271f2ac6b798d50f6c0ba8e022c589"
+        "sha": "62998f0adfb22b194e2dd633532e13bf27a79479"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "f8823dec98277a9516f2fb6fae9f58b3a59a23e1"
+        "sha": "9602086c6c5b05db77950c7f7495a2a3868f3537"
       }
     }
   ],
@@ -24,6 +24,7 @@
     ".github/release-please.yml",
     ".github/trusted-contribution.yml",
     ".github/workflows/ci.yaml",
+    ".github/workflows/samples.yaml",
     ".kokoro/build.bat",
     ".kokoro/build.sh",
     ".kokoro/coerce_logs.sh",