Update DOCtor-RST to 1.77.0 and enable NoRelativeDocPath rule

- Require DOCtor-RST 1.77.0
- Enable no_relative_doc_path rule to ensure :doc: directives use absolute paths

Author: OskarStark

.doctor-rst.yaml

@@ -63,6 +63,7 @@ rules:
     no_namespace_after_use_statements: ~
     no_non_breaking_space: ~
     no_php_open_tag_in_code_block_php_directive: ~
+    no_relative_doc_path: ~
     no_space_before_self_xml_closing_tag: ~
     no_typographic_quotes: ~
     non_static_phpunit_assertions: ~

.github/workflows/ci.yaml

@@ -72,7 +72,7 @@ jobs:
                     key: ${{ runner.os }}-doctor-rst-${{ steps.extract_base_branch.outputs.branch }}
 
             -   name: "Run DOCtor-RST"
-                uses: docker://oskarstark/doctor-rst:1.76.0
+                uses: docker://oskarstark/doctor-rst:1.77.0
                 with:
                     args: --short --error-format=github --cache-file=/github/workspace/.cache/doctor-rst.cache