Merge pull request #1663 from zcash/pczt-no-std #6279

Job	Run time
Test no-Orchard on Linux	4m 49s
Test Orchard on Linux	6m 38s
Test NU7 on Linux	6m 42s
Check ZFuture build on Linux	24s
Check ZFuture build on macOS	33s
Check ZFuture build on Windows	2m 48s
Test no-Orchard on macOS	7m 3s
Test Orchard on macOS	10m 32s
Test no-Orchard on Windows	11m 0s
Test Orchard on Windows	14m 28s
Test NU7 on Windows	14m 50s
Slow Test Orchard on Linux	4m 30s
Slow Test NU7 on Linux	4m 43s
Bitrot check	1m 34s
Latest build on ubuntu-latest	2m 16s
Build target wasm32-wasi	54s
Latest build on windows-latest	5m 10s
Latest build on macOS-latest	1m 57s
Clippy (MSRV)	1m 19s
Clippy (beta)	12s
Code coverage	1h 39m 43s
Intra-doc links	2m 12s
Rustfmt	14s
protobuf consistency	1m 6s
UUID validity	8s
Required status checks have passed	1s
	3h 25m 46s

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