Cache intermediate values for Edwards addition #354

Job	Run time
docker-master	1h 40m 32s
publish-standalone-dry-run	16s
test-standalone (master, dev, default)	55s
build-wasm-of-ocaml (master, 4.14.1)	15m 39s
build-js-of-ocaml (master, 4.11.1)	20m 4s
generated-files (master)	22m 36s
test-amd64	2h 19m 52s
standalone-haskell (master)	52m 3s
validate-docker-master	1m 14s
deploy-js-wasm-of-ocaml	52s
docker-check-all	4s
	5h 54m 7s

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