test: update WPT for WebCryptoAPI to 6a1c545d77 #4174

Job	Run time
Build slim tarball	1m 53s
x86_64-linux: with shared libraries	22m 17s
aarch64-darwin: with shared libraries	22m 11s
aarch64-linux: with shared libraries	18m 25s
x86_64-darwin: with shared libraries	35m 9s
	1h 39m 55s

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