[Suggestion] Suppress error output when GitHub version check fails

Expected Behaviour

The faas-cli failing to check whether it is the latest version does not affect the operation of the downloaded binary. If an error is encountered encourage the user to check manually, rather than distracting them with a verbose error message.

Current Behaviour

$ faas version
  ___                   _____           ____
 / _ \ _ __   ___ _ __ |  ___|_ _  __ _/ ___|
| | | | '_ \ / _ \ '_ \| |_ / _` |/ _` \___ \
| |_| | |_) |  __/ | | |  _| (_| | (_| |___) |
 \___/| .__/ \___|_| |_|_|  \__,_|\__,_|____/
      |_|

CLI:
 commit:  2cec97955a254358de5443987bedf8ceee272cf8
 version: 0.13.9
Unable to find latest version online error: Head "https://github.com/openfaas/faas-cli/releases/latest": dial tcp 127.0.0.1:443: connect: connection refused

This is a forced error, so somewhat contrived, however a screenshot from a user is shown below:

Possible Solution

Suppress the error emitted here, or add additional detail to explain that the user can check by browsing to https://github.com/openfaas/faas-cli/releases/latest

https://github.com/openfaas/faas-cli/blob/7de6613ff8fcfa16961fec6b8a00408650a843ec/commands/version.go#L71

Context

Supporting a new user on Slack who on seeing the error thought they had encountered an error, effectively on step 1. By providing a more human message this false barrier to entry is removed.

Your Environment

• FaaS-CLI version ( Full output from: faas-cli version ):

faas version
  ___                   _____           ____
 / _ \ _ __   ___ _ __ |  ___|_ _  __ _/ ___|
| | | | '_ \ / _ \ '_ \| |_ / _` |/ _` \___ \
| |_| | |_) |  __/ | | |  _| (_| | (_| |___) |
 \___/| .__/ \___|_| |_|_|  \__,_|\__,_|____/
      |_|

CLI:
 commit:  2cec97955a254358de5443987bedf8ceee272cf8
 version: 0.13.9

• Docker version ( Full output from: docker version ):
  n/a
• Are you using Docker Swarm (FaaS-swarm ) or Kubernetes (FaaS-netes)?
  n/a
• Operating System and version (e.g. Linux, Windows, MacOS):
  MacOS
• Link to your project or a code example to reproduce issue:
  n/a

Start in commands/version.go at the version-checking code linked in the issue, then run faas version with the online version check failing. Done means the command no longer emits a verbose error for this non-critical failure and instead provides a clear manual-check message, if applicable.