chore(deps): update dependency com_google_protobuf to v34 (#688)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[com_google_protobuf](https://redirect.github.com/protocolbuffers/protobuf)
| http_archive | major | `v33.5` → `v34.0` |

---

### Release Notes

<details>
<summary>protocolbuffers/protobuf (com_google_protobuf)</summary>

###
[`v34.0`](https://redirect.github.com/protocolbuffers/protobuf/compare/v34.0-rc2...v34.0)

[Compare
Source](https://redirect.github.com/protocolbuffers/protobuf/compare/v33.5...v34.0-rc2)

</details>

---

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tests/WORKSPACE

@@ -334,9 +334,9 @@ http_archive(
 
 http_archive(
     name = "com_google_protobuf",
-    sha256 = "98bc55acbc30be2bda6fb8bc9169a31e14956bd3b3169c63edbe6207b8116b68",
-    strip_prefix = "protobuf-33.5",
-    urls = ["https://github.com/protocolbuffers/protobuf/releases/download/v33.5/protobuf-33.5.zip"],
+    sha256 = "2f3c0e4327b34ff34d1315a885d539f5772726acc1b847a1a3f632657fec07c0",
+    strip_prefix = "protobuf-34.0",
+    urls = ["https://github.com/protocolbuffers/protobuf/releases/download/v34.0/protobuf-34.0.zip"],
 )
 
 load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")