perf(cli): optimize CPU consumption of help pages (#9607)

This change reduces the CPU consumption of --help by ~50%.

Also, this change removes ANSI escape codes from our golden files. I
don't think those were worth the inability to parallelize golden file tests and
global state fragility.

cli/testdata/coder_publickey_--help.golden

@@ -1,18 +1,18 @@
 coder v0.0.0-devel
 
-USAGE:
+USAGE:
   coder publickey [flags]
 
   Output your Coder public key used for Git operations
 
   Aliases: pubkey
 
-OPTIONS:
-      --reset bool
+OPTIONS:
+      --reset bool
           Regenerate your public key. This will require updating the key on any
           services it's registered with.
 
-  -y, --yes bool
+  -y, --yes bool
           Bypass prompts.
 
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