Fix user name with space on Windows

[lebenasa]

As a Windows user, the script doesn't run for me because I have a space in my user name. Adding quotes on affected variables fixed that for me.

Error log:

C:\Users\Leben Asa\dev\codewatch>docker run -it --rm --network host     --mount "type=bind,src=C:\Users\Leben Asa\dev\codewatch,dst=/repo"     --mount "type=bind,src=C:\Users\Leben Asa,dst=/home"     " -e SQITCH_ORIG_SYSUSER=Leben Asa -e SQITCH_ORI
G_EMAIL=Leben Asa@DESKTOP-C72NDQB -e TZ="SE Asia Standard Time" -e LESS=-R -e HOME=/home" sqitch/sqitch:latest --help
docker: invalid reference format: repository name must be lowercase.
See 'docker run --help'.

[theory]

Good find, thank you!