Removing fixed font size on style-rtl file too.

The changes made on this commit ensures that: 

* When adding a quote block to a page, the size that shows in the editor will be respected on the live page. This will be the default font size for the blockquote element.
* Custom font sizes will have higher specificity and will overwrite the default font size – above.
* When selecting one of the predefined font sizes (S, M, L, and XL), the classes that apply this change won't be overwritten by the default font size.

exford/style-rtl.css

@@ -1022,10 +1022,10 @@ footer {
  */
 blockquote {
 	padding-right: 16px;
+	font-size: 1.2rem;
 }
 
 blockquote p {
-	font-size: 1.2rem;
 	letter-spacing: normal;
 	line-height: 1.125;
 }
@@ -2101,7 +2101,6 @@ p.has-background {
 .wp-block-quote p {
 	font-family: "Source Sans Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
 	font-family: var(--font-headings, "Source Sans Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif);
-	font-size: 1.2rem;
 	letter-spacing: normal;
 	line-height: 1.125;
 }

exford/style.css

@@ -1022,10 +1022,10 @@ footer {
  */
 blockquote {
 	padding-left: 16px;
+	font-size: 1.2rem;
 }
 
 blockquote p {
-	font-size: 1.2rem;
 	letter-spacing: normal;
 	line-height: 1.125;
 }
@@ -2101,7 +2101,6 @@ p.has-background {
 .wp-block-quote p {
 	font-family: "Source Sans Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif;
 	font-family: var(--font-headings, "Source Sans Pro", -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen", "Ubuntu", "Cantarell", "Fira Sans", "Droid Sans", "Helvetica Neue", sans-serif);
-	font-size: 1.2rem;
 	letter-spacing: normal;
 	line-height: 1.125;
 }