Bump netty-all from 4.1.16.Final to 4.1.42.Final (#248)

Bumps [netty-all](https://github.com/netty/netty) from 4.1.16.Final to 4.1.42.Final.
<details>
<summary>Commits</summary>

- [`bd907c3`](https://github.com/netty/netty/commit/bd907c3b3acf3d746ad1143270224aa0f784cd1b) [maven-release-plugin] prepare release netty-4.1.42.Final
- [`2791f0f`](https://github.com/netty/netty/commit/2791f0fefac82663ca09dc8aa5dda024152c92f8) Avoid use of global AtomicLong for ScheduledFutureTask ids ([#9599](https://github-redirect.dependabot.com/netty/netty/issues/9599))
- [`86ff76a`](https://github.com/netty/netty/commit/86ff76a4f77662fe1bf61deeec5f3e39e16d4020) Fix incorrect comment  ([#9598](https://github-redirect.dependabot.com/netty/netty/issues/9598))
- [`5e69a13`](https://github.com/netty/netty/commit/5e69a13c21bcf89bf26dbf1421c5ec8188561a17) Cleanup JNI code to always correctly free memory when loading fails and also ...
- [`eb3c4bd`](https://github.com/netty/netty/commit/eb3c4bd926e697da3ea16079a5f4211adb375ea5) ChunkedNioFile can use absolute FileChannel::read to read chunks ([#9592](https://github-redirect.dependabot.com/netty/netty/issues/9592))
- [`76592db`](https://github.com/netty/netty/commit/76592db0bde9d4908191c2d7e54af3466ffd4673) Close eventfd shutdown/wakeup race by closely tracking epoll edges ([#9586](https://github-redirect.dependabot.com/netty/netty/issues/9586))
- [`0a2d85f`](https://github.com/netty/netty/commit/0a2d85f1d32749eb278b27502ba7de20de958485) Fix GraalVM native image build error ([#9593](https://github-redirect.dependabot.com/netty/netty/issues/9593))
- [`dc4de7f`](https://github.com/netty/netty/commit/dc4de7fbb4e17c606c92c542d5015042ada48e38) We need to use NewGloblRef when caching jclass instances ([#9595](https://github-redirect.dependabot.com/netty/netty/issues/9595))
- [`4499384`](https://github.com/netty/netty/commit/4499384135cdaca5ccdda85b0c9610d4ecd6c3cc) Update to netty-tcnative 2.0.26.Final ([#9589](https://github-redirect.dependabot.com/netty/netty/issues/9589))
- [`8648171`](https://github.com/netty/netty/commit/8648171abc27497d87a8b47e509e8adabd622f5b) Fix *SslEngineTest to not throw ClassCastException and pass in all cases ([#9588](https://github-redirect.dependabot.com/netty/netty/issues/9588))
- Additional commits viewable in [compare view](https://github.com/netty/netty/compare/netty-4.1.16.Final...netty-4.1.42.Final)
</details>
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diff --git a/pom.xml b/pom.xml
index a414caa..8944e0a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -53,7 +53,7 @@
     <protobuf.version>2.5.0</protobuf.version>
     <hadoop.version>2.7.2</hadoop.version>
     <log4j.configuration>file://log4j.properties</log4j.configuration>
-    <netty.version>4.1.16.Final</netty.version>
+    <netty.version>4.1.42.Final</netty.version>
     <guava.version>20.0</guava.version>
     <grpc.version>1.7.0</grpc.version>
     <jackson.version>2.8.8</jackson.version>