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This will cause a longer timeout when updating, but the fork apparently
causes performances issues

Update backend/build.sh; in util/update.sh don't exit when fetching artifacts from backend does not succeed (due to set -e)

Temporarily use cloogle branch of clean-platform which does not suffer from clean-compiler-and-rts/compiler#4

Update Syntax.icl

See merge request !217

In clean-compiler-and-rts/6b890e35e78c6cde75947593efd4b7776caf5b0b the restriction was lifted. It appeared that it forgot to copy it to the icl