Fix cask API tests

Library/Homebrew/test/cask/artifact/generic_artifact_spec.rb

@@ -19,7 +19,7 @@ RSpec.describe Cask::Artifact::Artifact, :cask do
   end
 
   context "without target" do
-    it "fails to load" do
+    it "fails to load", :no_api do
       expect do
         Cask::CaskLoader.load("invalid-generic-artifact-no-target")
       end.to raise_error(Cask::CaskInvalidError, /Generic Artifact.*requires.*target/)

Library/Homebrew/test/cask/artifact/manpage_spec.rb

@@ -6,7 +6,7 @@ RSpec.describe Cask::Artifact::Manpage, :cask do
   context "without section" do
     let(:cask_token) { "invalid-manpage-no-section" }
 
-    it "fails to load a cask without section" do
+    it "fails to load a cask without section", :no_api do
       expect { cask }.to raise_error(Cask::CaskInvalidError, /is not a valid man page name/)
     end
   end

Library/Homebrew/test/cask/audit_spec.rb

@@ -503,7 +503,7 @@ RSpec.describe Cask::Audit, :cask do
       end
     end
 
-    describe "livecheck should be skipped" do
+    describe "livecheck should be skipped", :no_api do
       let(:only) { ["livecheck_version"] }
       let(:online) { true }
       let(:message) { /Version '[^']*' differs from '[^']*' retrieved by livecheck\./ }

Library/Homebrew/test/cask/cask_loader/from_tap_loader_spec.rb

@@ -24,7 +24,7 @@ RSpec.describe Cask::CaskLoader::FromTapLoader do
       expect { described_class.new("foo/bar/baz").load(config: nil) }.to raise_error(Cask::CaskUnavailableError)
     end
 
-    context "with sharded Cask directory" do
+    context "with sharded Cask directory", :no_api do
       let(:cask_path) { tap.cask_dir/cask_name[0]/"#{cask_name}.rb" }
 
       it "returns a Cask" do

Library/Homebrew/test/cask/dsl_spec.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-RSpec.describe Cask::DSL, :cask do
+RSpec.describe Cask::DSL, :cask, :no_api do
   let(:cask) { Cask::CaskLoader.load(token) }
   let(:token) { "basic-cask" }