haml 6.0.0.beta.2 does not work with middleman even 5.x

Signed-off-by: Takuya Noguchi <takninnovationresearch@gmail.com>

Gemfile

@@ -11,7 +11,7 @@ gem "middleman-syntax"
 
 ## Template engines
 gem "builder"
-gem "haml", "~> 5.2.2"
+gem "haml", ">= 6.0.0.beta.2"
 gem "kramdown"
 
 # Rake tasks
@@ -27,6 +27,6 @@ group :development do
   gem "pry"
   gem "pry-byebug"
 
-  gem "haml_lint", "~> 0.40"
+  gem "haml_lint", github: "sds/haml-lint", branch: "main"
   gem "rubocop"
 end

Gemfile.lock

@@ -8,6 +8,18 @@ GIT
       mini_racer (~> 0.5)
       nokogiri (~> 1.6)
 
+GIT
+  remote: https://github.com/sds/haml-lint.git
+  revision: b338aa55ab544968b6a12d236415b3377a595503
+  branch: main
+  specs:
+    haml_lint (0.40.1)
+      haml (>= 4.0, < 6.1)
+      parallel (~> 1.10)
+      rainbow
+      rubocop (>= 0.50.0)
+      sysexits (~> 1.1)
+
 GIT
   remote: https://github.com/tnir/middleman.git
   revision: 80f9122a88c770a11726df4cd459c8b8acc7c166
@@ -77,15 +89,10 @@ GEM
     faraday-net_http (3.0.0)
     fastimage (2.2.6)
     ffi (1.15.5)
-    haml (5.2.2)
-      temple (>= 0.8.0)
+    haml (6.0.0.beta.2)
+      temple (>= 0.8.2)
+      thor
       tilt
-    haml_lint (0.40.1)
-      haml (>= 4.0, < 5.3)
-      parallel (~> 1.10)
-      rainbow
-      rubocop (>= 0.50.0)
-      sysexits (~> 1.1)
     hamster (3.0.0)
       concurrent-ruby (~> 1.0)
     hashie (5.0.0)
@@ -203,8 +210,8 @@ PLATFORMS
 
 DEPENDENCIES
   builder
-  haml (~> 5.2.2)
-  haml_lint (~> 0.40)
+  haml (>= 6.0.0.beta.2)
+  haml_lint!
   kramdown
   middleman!
   middleman-blog