Enable React Router Sixth Page test to avoid merge conflicts

The master branch has this test marked as skip expecting it to be fixed in
this branch. Enabling it (removing the skip) avoids merge conflicts and lets
CI show whether the test passes or fails with the body duplication fix.

Also includes Capybara best practices fixes from rubocop autofix:
- Use have_no_content instead of not_to have_content
- Use have_no_text instead of not_to have_text
- Add disable comments for pre-existing ClickLinkOrButtonStyle violations

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: justin808

react_on_rails_pro/spec/dummy/spec/system/integration_spec.rb

@@ -11,7 +11,7 @@ def change_text_expect_dom_selector(dom_selector, expect_no_change: false)
     find("input").set new_text
     within("h3") do
       if expect_no_change
-        expect(subject).not_to have_content new_text
+        expect(subject).to have_no_content new_text
       else
         expect(subject).to have_content new_text
       end
@@ -110,7 +110,7 @@ def change_text_expect_dom_selector(dom_selector, expect_no_change: false)
   it "changes name in message according to input" do
     visit "/client_side_hello_world"
     change_text_expect_dom_selector("#HelloWorld-react-component-0")
-    click_link "Hello World Component Server Rendered, with extra options"
+    click_link "Hello World Component Server Rendered, with extra options" # rubocop:disable Capybara/ClickLinkOrButtonStyle
     change_text_expect_dom_selector("#my-hello-world-id")
   end
 end
@@ -174,19 +174,19 @@ def change_text_expect_dom_selector(dom_selector, expect_no_change: false)
 
   before do
     visit "/"
-    click_link "React Router"
+    click_link "React Router" # rubocop:disable Capybara/ClickLinkOrButtonStyle
   end
 
   context "when rendering /react_router" do
     it { is_expected.to have_text("Woohoo, we can use react-router here!") }
 
     it "clicking links correctly renders other pages" do
-      click_link "Router First Page"
+      click_link "Router First Page" # rubocop:disable Capybara/ClickLinkOrButtonStyle
       expect(page).to have_current_path("/react_router/first_page")
       first_page_header_text = page.find(:css, "h2#first-page").text
       expect(first_page_header_text).to eq("React Router First Page")
 
-      click_link "Router Second Page"
+      click_link "Router Second Page" # rubocop:disable Capybara/ClickLinkOrButtonStyle
       expect(page).to have_current_path("/react_router/second_page")
       second_page_header_text = page.find(:css, "h2#second-page").text
       expect(second_page_header_text).to eq("React Router Second Page")
@@ -239,12 +239,12 @@ def change_text_expect_dom_selector(dom_selector, expect_no_change: false)
   end
 end
 
-describe "Manual client hydration", :js, type: :system do
+describe "Manual client hydration", :js do
   before { visit "/xhr_refresh" }
 
   it "HelloWorldRehydratable onChange should trigger" do
     within("form") do
-      click_button "refresh"
+      click_button "refresh" # rubocop:disable Capybara/ClickLinkOrButtonStyle
     end
     within("#HelloWorldRehydratable-react-component-1") do
       find("input").set "Should update"
@@ -407,18 +407,18 @@ def change_text_expect_dom_selector(dom_selector, expect_no_change: false)
     # Ensure that the component state is not updated
     change_text_expect_dom_selector(selector, expect_no_change: true)
 
-    expect(page).not_to have_text "Loading branch1"
-    expect(page).not_to have_text "Loading branch2"
-    expect(page).not_to have_text(/Loading branch1 at level \d+/)
+    expect(page).to have_no_text "Loading branch1"
+    expect(page).to have_no_text "Loading branch2"
+    expect(page).to have_no_text(/Loading branch1 at level \d+/)
     expect(page).to have_text(/branch1 \(level \d+\)/, count: 5)
   end
 
   it "doesn't hydrate status component if packs are not loaded" do
     # visit waits for the page to load, so we ensure that the page is loaded before checking the hydration status
     visit "#{path}?skip_js_packs=true"
     expect(page).to have_text "HydrationStatus: Streaming server render"
-    expect(page).not_to have_text "HydrationStatus: Hydrated"
-    expect(page).not_to have_text "HydrationStatus: Page loaded"
+    expect(page).to have_no_text "HydrationStatus: Hydrated"
+    expect(page).to have_no_text "HydrationStatus: Page loaded"
   end
 end