docs(upgrade): Update links to v6 variable changes.

Author: edonehoo

packages/documentation-site/patternfly-docs/content/get-started/upgrade.md

@@ -66,7 +66,7 @@ We recommend *completely* removing CSS overrides as much as possible, so that yo
 If you do need to keep any CSS customizations, continue to step 3 and follow the instructions to [review and update variable and class names](#3.-review-and-update-variable-and-class-names) and make sure you are using what's most appropriate.
 
 ### 3. Review and update variable and class names
-A number of variables were removed or added with PatternFly 6, primarily due to logical direction changes, refactoring, or deprecation. For more context, we've put together a list of [variables that have been removed](https://docs.google.com/spreadsheets/d/e/2PACX-1vQQLWzMGQTAFHr6ClxoOZPpSNhP-frqu9w0DBzFJG0SOyBKKvjVV5wqz2o_Nh6jnO73oiXH259t5-V0/pubhtml?gid=673459372&single=true) and a list of [variables that have been added](https://docs.google.com/spreadsheets/d/e/2PACX-1vQQLWzMGQTAFHr6ClxoOZPpSNhP-frqu9w0DBzFJG0SOyBKKvjVV5wqz2o_Nh6jnO73oiXH259t5-V0/pubhtml?gid=0&single=true).
+A number of variables were removed or added with PatternFly 6, primarily due to logical direction changes, refactoring, or deprecation. For more context, we've put together a list of [variables that have been removed](https://docs.google.com/spreadsheets/d/e/2PACX-1vQqeH7ThYi0jkhYEB8B2SXa7x8AaY5T9ajG6o-Ogz3p7YVp0OuTulb_L3DYLDrHlY4zUE3IBiup6tkN/pubhtml?gid=1160160856&single=true) and a list of [variables that have been added](https://docs.google.com/spreadsheets/d/e/2PACX-1vQqeH7ThYi0jkhYEB8B2SXa7x8AaY5T9ajG6o-Ogz3p7YVp0OuTulb_L3DYLDrHlY4zUE3IBiup6tkN/pubhtml?gid=268831450&single=true).
 
 Wherever you have any custom CSS overrides that reference PatternFly class names or CSS variables, you should carefully review them and make updates to ensure that they align with our new design tokens, as described in [our tokens documentation](/tokens/all-patternfly-tokens).