Define a limited set of filters for SingleLinePipeline

Removes the following filters from its parent GfmPipeline:

- SyntaxHighlightFilter
- UploadLinkFilter
- TableOfContentsFilter
- LabelReferenceFilter
- TaskListFilter

Closes #1697

lib/banzai/pipeline/single_line_pipeline.rb

@@ -3,7 +3,23 @@ require 'banzai'
 module Banzai
   module Pipeline
     class SingleLinePipeline < GfmPipeline
+      def self.filters
+        @filters ||= [
+          Filter::SanitizationFilter,
+          Filter::EmojiFilter,
+          Filter::AutolinkFilter,
+          Filter::ExternalLinkFilter,
+
+          Filter::UserReferenceFilter,
+          Filter::IssueReferenceFilter,
+          Filter::ExternalIssueReferenceFilter,
+          Filter::MergeRequestReferenceFilter,
+          Filter::SnippetReferenceFilter,
+          Filter::CommitRangeReferenceFilter,
+          Filter::CommitReferenceFilter,
+        ]
+      end
     end
   end
 end