clean up button border radius/width (aws-amplify#6127)

Author: hbuchel

src/styles/popover.scss

@@ -8,11 +8,11 @@
   background: var(--amplify-colors-background-primary);
   border-radius: var(--amplify-radii-medium);
   padding: var(--amplify-space-small);
-  border: 2px solid var(--amplify-colors-teal-80);
+  border: 1px solid var(--amplify-colors-teal-80);
   box-shadow: 0 1px 3px hsla(0, 0, 0, 0.3);
   min-width: 14rem;
   top: 100%;
-  transform: translate(0, -2px);
+  transform: translate(0, -1px);
   right: 0;
   &:focus-visible {
     outline: 2px solid var(--amplify-colors-border-focus);
@@ -52,6 +52,6 @@
   }
   100% {
     opacity: 1;
-    transform: translate(0, -2px);
+    transform: translate(0, -1px);
   }
 }

src/styles/split-button.scss

@@ -1,5 +1,5 @@
 .split-button {
-  gap: var(--amplify-space-xxxs);
+  gap: 2px;
 }
 
 .split-button__start {

src/themes/baseTheme.ts

@@ -44,8 +44,7 @@ export const baseTheme = createTheme({
     },
     components: {
       button: {
-        borderRadius: { value: '{radii.large}' },
-        borderWidth: { value: '{borderWidths.medium}' },
+        borderRadius: { value: '{radii.medium}' },
         borderColor: { value: '{colors.brand.primary.80}' },
         backgroundColor: { value: '{colors.background.primary}' },
         color: { value: '{colors.brand.primary.80}' },