bug(deeplinking): escaping breaks whitespaces & underscored tags/ids (via #4953)

* add tests for operation lacking an operationId
* add deep linking tests for tags/operationIds with underscores
* migrate from `_` to `%20` for deeplink hash whitespace escaping
* add backwards compatibility for `_` whitespace escaping
* update util unit tests

test/e2e-cypress/static/documents/features/deep-linking.openapi.yaml

@@ -18,6 +18,29 @@ paths:
       operationId: "my Operation"
       tags: ["my Tag"]
       summary: an operation
+      responses:
+        '200':
+          description: a pet to be returned
+          content: 
+            application/json:
+              schema:
+                type: object
+  /withUnderscores:
+    patch:
+      operationId: "underscore_Operation"
+      tags: ["underscore_Tag"]
+      summary: an operation
+      responses:
+        '200':
+          description: a pet to be returned
+          content: 
+            application/json:
+              schema:
+                type: object
+  /noOperationId:
+    put:
+      tags: ["tagTwo"]
+      summary: some operations are anonymous...
       responses:
         '200':
           description: a pet to be returned

test/e2e-cypress/static/documents/features/deep-linking.swagger.yaml

@@ -17,3 +17,18 @@ paths:
       responses:
         "200":
           description: ok
+  /withUnderscores:
+    patch:
+      operationId: "underscore_Operation"
+      tags: ["underscore_Tag"]
+      summary: an operation
+      responses:
+        "200":
+          description: ok
+  /noOperationId:
+    put:
+      tags: ["tagTwo"]
+      summary: an operation
+      responses:
+        "200":
+          description: ok