chore: regenerate README (#307)

This PR was generated using Autosynth. 🌈


<details><summary>Log from Synthtool</summary>

```
2020-10-19 22:58:17,777 synthtool [DEBUG] > Executing /root/.cache/synthtool/java-monitoring/.github/readme/synth.py.
On branch autosynth-readme
nothing to commit, working directory clean
2020-10-19 22:58:18,721 synthtool [DEBUG] > Wrote metadata to .github/readme/synth.metadata/synth.metadata.

```
</details>

Full log will be available here:
https://source.cloud.google.com/results/invocations/fe568ff3-c700-4174-aad2-cfdcfa9a4c2e/targets

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

.github/readme/synth.metadata/synth.metadata

@@ -4,14 +4,14 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/java-monitoring.git",
-        "sha": "ca68d8aa7ab3d257f6f4eeab78b57d94d20ca6b6"
+        "sha": "86bc6a002068662efe38e23a7e75b3f5592abb53"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "d5d03413e1879108b5ade8839ce38de01be652da"
+        "sha": "6dc98b26a9c823e92fa21455fb6e5862613c49c2"
       }
     }
   ]

README.md

@@ -39,7 +39,7 @@ If you are using Maven without BOM, add this to your dependencies:
 <dependency>
   <groupId>com.google.cloud</groupId>
   <artifactId>google-cloud-monitoring</artifactId>
-  <version>2.0.5-SNAPSHOT</version>
+  <version>2.0.5</version>
 </dependency>
 
 ```