fix(theme/Button): remove border color for solid variant

Author: TylerAPfledderer

src/@chakra-ui/gatsby-plugin/components/Button.ts

@@ -38,6 +38,7 @@ const baseStyle = defineStyle((props) => ({
 const variantSolid = defineStyle({
   color: "background.base",
   bg: "primary.base",
+  borderColor: "transparent",
   _hover: {
     color: "background.base",
     bg: "primary.hover",