Bug fix: fix --log-level help rendering

[dandavison]

What was changed

Remove backticks that were causing broken --help rendering:

Before
Note spurious presence of "server start-dev" and lack of expected "string"

$ temporal --help | rg -C1 -F -- '--log-level'
                Log format. Accepted values: text, json. (default "text")
      --log-level server start-dev
                Log level. Default is "info" for most commands and "warn"

After

$ ./temporal --help | rg -C1 -F -- '--log-level'
                Log format. Accepted values: text, json. (default "text")
      --log-level string
                Log level. Default is "info" for most commands and "warn"

Why?

Bug