Try support windows path in ensureFileRegexMatches

Author: yhkee0404

tests/docs/smoke-all/2025/03/07/issue-12222/index.qmd

@@ -9,7 +9,7 @@ _quarto:
     html:
       ensureFileRegexMatches:
         - 
-          - '\<img src="posts/post-with-code/image.jpg'
-          - '\<img src="posts/welcome/thumbnail.jpg'
+          - '\<img src="posts[/|\\]post-with-code[/|\\]image.jpg'
+          - '\<img src="posts[/|\\]welcome[/|\\]thumbnail.jpg'
         - []
 ---

tests/docs/smoke-all/2025/03/07/issue-12222/posts/preview-image-and-empty-meta-image/index.qmd

@@ -7,8 +7,8 @@ _quarto:
     html:
       ensureFileRegexMatches:
         - 
-          - '\<meta name="twitter:image" content="../../posts/welcome/thumbnail.jpg'
-          - '\<meta property="og:image" content="../../posts/welcome/thumbnail.jpg'
+          - '\<meta name="twitter:image" content="../..[/|\\]posts/welcome/thumbnail.jpg'
+          - '\<meta property="og:image" content="../..[/|\\]posts/welcome/thumbnail.jpg'
         - []
 image: ""
 ---

tests/docs/smoke-all/2025/03/07/issue-12222/posts/preview-image-and-no-meta-image/index.qmd

@@ -7,8 +7,8 @@ _quarto:
     html:
       ensureFileRegexMatches:
         - 
-          - '\<meta name="twitter:image" content="../../posts/post-with-code/image.jpg'
-          - '\<meta property="og:image" content="../../posts/post-with-code/image.jpg'
+          - '\<meta name="twitter:image" content="../..[/|\\]posts/post-with-code/image.jpg'
+          - '\<meta property="og:image" content="../..[/|\\]posts/post-with-code/image.jpg'
         - []
 ---