fix(material-experimental): rename theme files to match stable components (#18383)

* fix(material-experimental): rename theme files to match stable components

* fix case of slider theme

Author: andrewseguin

src/dev-app/theme.scss

@@ -1,8 +1,8 @@
 @import '../material/core/theming/all-theme';
+@import '../material-experimental/mdc-slider/slider-theme';
 @import '../material/core/focus-indicator/focus-indicator';
 @import '../material-experimental/column-resize/column-resize';
 @import '../material-experimental/mdc-helpers/mdc-helpers';
-@import '../material-experimental/mdc-slider/mdc-slider';
 @import '../material-experimental/mdc-theming/all-theme';
 @import '../material-experimental/mdc-typography/all-typography';
 @import '../material-experimental/popover-edit/popover-edit';

src/material-experimental/mdc-autocomplete/_mdc-autocomplete.scss renamed to src/material-experimental/mdc-autocomplete/_autocomplete-theme.scss

@@ -34,7 +34,7 @@ ng_module(
 sass_library(
     name = "mdc_form_field_scss_lib",
     srcs = [
-        "_mdc-form-field.scss",
+        "_form-field-theme.scss",
         "_mdc-text-field-theme-variable-refresh.scss",
     ],
     deps = [