Fix error message if name is invalid

Author: remcohaszing

src/remark-mdx-frontmatter.ts

@@ -37,7 +37,7 @@ const remarkMdxFrontmatter: Plugin<[RemarkMdxFrontmatterOptions?], Root> = ({
   parsers
 } = {}) => {
   if (!isIdentifierName(name)) {
-    throw new Error(`Name this should be a valid identifier, got: ${JSON.stringify(name)}`)
+    throw new Error(`Name should be a valid identifier, got: ${JSON.stringify(name)}`)
   }
 
   const allParsers: FrontmatterParsers = {

src/test.ts

@@ -61,6 +61,6 @@ test('invalid name', () => {
         remarkPlugins: [remarkFrontmatter, [remarkMdxFrontmatter, { name: 'Not valid' }]],
         jsx: true
       }),
-    'If name is specified, this should be a valid identifier name, got: "Not valid"'
+    /Name should be a valid identifier, got: "Not valid"/
   )
 })