implement dot for higher-dimensional arrays with Ix2 #672

Job	Run time
clippy/stable	24s
docs/nightly	20s
Pass MSRV values to other jobs	4s
miri	11m 4s
cross_test/s390x-unknown-linux-gnu/stable	9m 19s
cross_test/i686-unknown-linux-gnu/stable	2m 45s
format/nightly	15s
nostd/thumbv6m-none-eabi/stable	20s
cargo-careful	2m 8s
blas-msrv	1m 2s
tests/stable	2m 56s
tests/nightly	3m 34s
tests/beta	2m 52s
tests/1.87.0	2m 56s
conclusion	0s
	39m 59s

Provide feedback