Spellcheck: also ignore code blocks inside blockquotes

The existing regex pattern for ignoring code blocks only matched
blocks at the start of a line (with optional whitespace). This
update makes it also match code blocks inside markdown
blockquotes, where lines are prefixed with `>`.

Author: rodrigoprimo

.cspell.yml

@@ -12,9 +12,9 @@ patterns:
   - name: markdown_code_block
     pattern: |
       /
-          ^(\s*`{3,})[a-z]+   # match the ``` with a language modifier
-          [\s\S]*?            # the block of code
-          ^\1                 # end of the block
+          ^((?:>\s*)?`{3,})[a-z]+  # match the ``` with a language modifier, optionally inside a blockquote
+          [\s\S]*?                  # the block of code
+          ^\1                       # end of the block
       /gmx
   - name: markdown_inline_code
     pattern: /(\s*`)[^`\n]{3,}`/gmx