update-tests-metdata failing due to invalid byte sequence

This has been happening quite a bit on master recently (e.g. https://gitlab.com/gitlab-org/gitlab-ce/-/jobs/224364661):

/usr/local/bundle/gems/pg-1.1.4/lib/pg/connection.rb:173:in `get_last_result': ERROR:  invalid byte sequence for encoding "UTF8": 0x00 (PG::CharacterNotInRepertoire)
CONTEXT:  COPY spec_profiling_results, line 1193
	from /usr/local/bundle/gems/pg-1.1.4/lib/pg/connection.rb:173:in `copy_data'
	from /usr/local/bundle/gems/postgres-copy-1.4.1/lib/postgres-copy/acts_as_copy_target.rb:103:in `copy_from'
	from scripts/insert-rspec-profiling-data:42:in `block in insert_data'
	from scripts/insert-rspec-profiling-data:40:in `each'
	from scripts/insert-rspec-profiling-data:40:in `insert_data'
	from scripts/insert-rspec-profiling-data:47:in `<main>'