fix(deps): update dependency @google-cloud/common to v3 (googleapis#421)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [@google-cloud/common](https://github.com/googleapis/nodejs-common) | dependencies | major | [`^2.3.0` -> `^3.0.0`](https://renovatebot.com/diffs/npm/@google-cloud%2fcommon/2.4.0/3.0.0) |

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### Release Notes

<details>
<summary>googleapis/nodejs-common</summary>

### [`v3.0.0`](https://github.com/googleapis/nodejs-common/blob/master/CHANGELOG.md#&#8203;300-httpswwwgithubcomgoogleapisnodejs-commoncomparev240v300-2020-03-26)

[Compare Source](https://github.com/googleapis/nodejs-common/compare/v2.4.0...v3.0.0)

##### ⚠ BREAKING CHANGES

-   drop support for node.js 8 ([#&#8203;554](https://github.com/googleapis/nodejs-common/issues/554))
-   remove support for custom promises ([#&#8203;541](https://github.com/googleapis/nodejs-common/issues/541))

##### Features

-   add progress events ([#&#8203;540](https://www.github.com/googleapis/nodejs-common/issues/540)) ([1834059](https://www.github.com/googleapis/nodejs-common/commit/18340596ecb61018e5427371b9b5a120753ec003))

##### Bug Fixes

-   remove support for custom promises ([#&#8203;541](https://www.github.com/googleapis/nodejs-common/issues/541)) ([ecf1c16](https://www.github.com/googleapis/nodejs-common/commit/ecf1c167927b609f13dc4fbec1954ff3a2765344))
-   **deps:** update dependency [@&#8203;google-cloud/projectify](https://github.com/google-cloud/projectify) to v2 ([#&#8203;553](https://www.github.com/googleapis/nodejs-common/issues/553)) ([23030a2](https://www.github.com/googleapis/nodejs-common/commit/23030a25783cd091f4720c25a15416c91e7bd0a0))
-   **deps:** update dependency [@&#8203;google-cloud/promisify](https://github.com/google-cloud/promisify) to v2 ([#&#8203;552](https://www.github.com/googleapis/nodejs-common/issues/552)) ([63175e0](https://www.github.com/googleapis/nodejs-common/commit/63175e0c4504020466a95e92c2449bdb8ac47546))

##### Miscellaneous Chores

-   drop support for node.js 8 ([#&#8203;554](https://www.github.com/googleapis/nodejs-common/issues/554)) ([9f41047](https://www.github.com/googleapis/nodejs-common/commit/9f410477432893f68e57b5eeb31a068a3d8ef52f))

</details>

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package.json

@@ -36,7 +36,7 @@
     "prelint": "cd samples; npm link ../; npm i"
   },
   "dependencies": {
-    "@google-cloud/common": "^2.3.0",
+    "@google-cloud/common": "^3.0.0",
     "@google-cloud/paginator": "^3.0.0",
     "@google-cloud/projectify": "^2.0.0",
     "@google-cloud/promisify": "^2.0.0",