Clean up and make consistent how config is passed to JS #409

Job	Run time
test (bl { "git": "https://github.com/projectblacklight/blacklight.git" } / rails ~> 8.0.0 / rb 3.3 / importmap-rails)	2m 50s
test (bl { "git": "https://github.com/projectblacklight/blacklight.git" } / rails ~> 8.0.0 / rb 3.3 / esbuild)	3m 13s
test (bl ~> 8.0 / rails 7.2.1 / rb 3.3 / importmap-rails, sprockets)	3m 17s
test (bl ~> 8.0 / rails 7.2.1 / rb 3.3 / importmap-rails, propshaft)	2m 45s
test (bl ~> 8.0 / rails 7.2.1 / rb 3.3 / esbuild, propshaft)	3m 1s
test (bl ~> 7.0 / rails 7.2.1 / rb 3.3 / esbuild, sprockets)	3m 36s
test (bl ~> 7.0 / rails 7.2.1 / rb 3.3 / esbuild, propshaft)	3m 2s
test (bl ~> 7.0 / rails 7.1.4 / rb 3.2 / esbuild, sprockets)	3m 52s
test (bl ~> 7.0 / rails 7.0.8.4 / rb 3.1 / esbuild, sprockets)	3m 50s
	29m 26s

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