fix(theme): Fixed rmd-theme-get-swatch to loop over all rmd-theme-colors instead of the primaries only

I probably should have added some other `@if`s to this after the
looping to ensure a color has been found, but the checks before this
point should really catch the other cases.

Because this only looped over the primary colors, if you set the
`$rmd-theme-primary: $rmd-green-500;`, this color would be resolved as
`$rmd-green-500-300` in the chip package for the
`$rmd-chip-themed-background-color` variable which threw an error when
trying to do color contrast ratio fixes in `$rmd-chip-themed-color`.

Closes #884

Author: mlaursen

packages/theme/src/_functions.scss

@@ -84,7 +84,7 @@
   } @else {
     $index: 1;
     $found: false;
-    @while not $found and $index < length($rmd-theme-primary-suffixes) {
+    @while not $found and $index < length($rmd-theme-colors) {
       $suffix: nth($rmd-theme-colors, $index);
       $suffix-index: str-index($current-color-name, $suffix);
       @if $suffix-index {