[Fix] string quotes issue in doc-builder notebook-to-mdx (#471)

Author: mishig25

.github/workflows/build_main_documentation.yml

@@ -156,7 +156,7 @@ jobs:
         if: inputs.convert_notebooks
         run: |
           cd doc-builder
-          doc-builder notebook-to-mdx ${{ env.doc_folder }}"
+          doc-builder notebook-to-mdx ${{ env.doc_folder }}
           cd ..
 
       - name: Make documentation

.github/workflows/build_pr_documentation.yml

@@ -142,7 +142,7 @@ jobs:
         if: inputs.convert_notebooks
         run: |
           cd doc-builder
-          doc-builder notebook-to-mdx ${{ env.doc_folder }}"
+          doc-builder notebook-to-mdx ${{ env.doc_folder }}
           cd ..
 
       - name: Make documentation