chore: release 2.6.0 (#182)

🤖 I have created a release \*beep\* \*boop\*
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## [2.6.0](https://www.github.com/googleapis/nodejs-document-ai/compare/v2.5.0...v2.6.0) (2021-03-15)


### Features

* remove the translation fields in document.proto ([#181](https://www.github.com/googleapis/nodejs-document-ai/issues/181)) ([d76272a](https://www.github.com/googleapis/nodejs-document-ai/commit/d76272a98f527d00a5862299208f8f0ebb054405))
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This PR was generated with [Release Please](https://github.com/googleapis/release-please). See [documentation](https://github.com/googleapis/release-please#release-please).

document-ai/package.json

@@ -13,7 +13,7 @@
     "test": "mocha test/*.js --timeout 600000"
   },
   "dependencies": {
-    "@google-cloud/documentai": "^2.5.0",
+    "@google-cloud/documentai": "^2.6.0",
     "@google-cloud/storage": "^5.0.0",
     "p-queue": "^6.6.2",
     "uuid": "^8.3.1"