Add release profile

[lukewilliamboswell]

This PR

• Add a release profile for cargo so that optimised builds are significantly smaller

Before change

17:16:21 ~/Documents/GitHub/basic-webserver release-profile $ roc build --optimize examples/echo.roc 
🔨 Rebuilding platform...
0 errors and 0 warnings found in 21972 ms while successfully building:

    examples/echo
17:17:22 ~/Documents/GitHub/basic-webserver release-profile $ ls -hl examples/echo 
-rwxr-xr-x  1 luke  staff   9.3M 18 Nov 17:20 examples/echo

After change (with --optimize)

17:17:31 ~/Documents/GitHub/basic-webserver release-profile $ roc build --optimize examples/echo.roc
🔨 Rebuilding platform...
0 errors and 0 warnings found in 5589 ms while successfully building:

    examples/echo
17:17:44 ~/Documents/GitHub/basic-webserver release-profile $ ls -hl examples/echo                  
-rwxr-xr-x  1 luke  staff   7.2M 18 Nov 17:17 examples/echo