Update cheatsheets

mosquitto_sub

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+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# mosquitto_sub
+
+> A simple MQTT version 3.1.1 client that will subscribe to topics and print the messages that it receives.
+> More information: <https://mosquitto.org/man/mosquitto_sub-1.html>.
+
+- Subscribe to the topic `sensors/temperature` information with Quality of Service (`QoS`) set to 1. (The default hostname is `localhost` and port 1883):
+
+`mosquitto_sub -t {{sensors/temperature}} -q {{1}}`
+
+- Subscribe to all broker status messages publishing on `iot.eclipse.org` port 1885 and print published messages verbosely:
+
+`mosquitto_sub -v -h "iot.eclipse.org" -p 1885 -t {{\$SYS/#}}`
+
+- Subscribe to multiple topics matching a given pattern. (+ takes any metric name):
+
+`mosquitto_sub -t {{sensors/machines/+/temperature/+}}`