Update strum requirement from ^0.21 to ^0.26 #32

Job	Run time
lint / audit	12s
lint / audit	12s
test (nightly, --lib) / audit	1s
test (nightly, --lib) / audit	8s
test (nightly, --doc) / audit	1s
test (nightly, --doc) / audit	8s
test (nightly, --test evaluate) / audit	1s
test (nightly, --test evaluate) / audit	15s
test (nightly, --test versions) / audit	1s
test (nightly, --test versions) / audit	12s
test (stable, --lib) / audit	1s
test (stable, --lib) / audit	10s
test (stable, --test evaluate) / audit	1s
test (stable, --test evaluate) / audit	11s
test (stable, --test versions) / audit	1s
test (stable, --test versions) / audit	10s
test (stable, --test evaluate) / test	0s
test (stable, --test evaluate) / test	1m 8s
test (nightly, --test evaluate) / test	0s
test (nightly, --test evaluate) / test	1m 24s
test (nightly, --doc) / test	0s
test (nightly, --doc) / test	1m 11s
test (nightly, --lib) / test	0s
test (nightly, --lib) / test	3m 47s
test (stable, --test versions) / test	0s
test (stable, --test versions) / test	48s
test (stable, --lib) / test	0s
test (stable, --lib) / test	4m 3s
test (nightly, --test versions) / test	0s
test (nightly, --test versions) / test	53s
lint / check (stable)	22s
lint / check (stable)	22s
lint / fmt (stable)	4s
lint / fmt (stable)	4s
lint / fuzz-check	15s
lint / fuzz-check	15s
lint / check (nightly)	27s
lint / check (nightly)	27s
lint / clippy (stable)	27s
lint / clippy (stable)	27s
lint / fmt (nightly)	11s
lint / fmt (nightly)	11s
lint / clippy (nightly)	35s
lint / clippy (nightly)	35s
lint / docs	23s
lint / docs	23s
publish	0s
publish	0s
	20m 27s

Provide feedback