Fix Ubuntu/Debian setup when $PATH contains spaces (#9307)

* Change `echo` to `export`

* Add `export` as a note under the `echo` command

* Remove note from last commit

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update docs/newbs_getting_started.md

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update docs/newbs_getting_started.md

Add 1 line of whitespace under note

Co-authored-by: Ryan <fauxpark@gmail.com>

Co-authored-by: Ryan <fauxpark@gmail.com>

docs/newbs_getting_started.md

@@ -97,7 +97,7 @@ In most situations you will want to answer Yes to all of the prompts.
 It's possible, that you will get an error saying something like: `bash: qmk: command not found`.
 This is due to a [bug](https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=839155) Debian introduced with their Bash 4.4 release, which removed `$HOME/.local/bin` from the PATH. This bug was later fixed on Debian and Ubuntu.
 Sadly, Ubuntu reitroduced this bug and is [yet to fix it](https://bugs.launchpad.net/ubuntu/+source/bash/+bug/1588562).
-Luckily, the fix is easy. Run this as your user: `echo "PATH=$HOME/.local/bin:$PATH" >> $HOME/.bashrc && source $HOME/.bashrc`
+Luckily, the fix is easy. Run this as your user: `echo "PATH=$HOME/.local/bin:\"$PATH\"" >> $HOME/.bashrc && source $HOME/.bashrc`
 
 ?>**Note on FreeBSD**:
 It is suggested to run `qmk setup` as a non-`root` user to start with, but this will likely identify packages that need to be installed to your