Revert "crypto/sha1: add WriteString and WriteByte method"

Revert "crypto/sha1: add WriteString and WriteByte method"

This reverts CL 483815

Reason for revert: can cause cgo errors when using boringcrypto.
See #59954.

For #38776
For #59954

Change-Id: I1f7e0fb06b627971811623927e3d98c0fdbc730b
Reviewed-on: https://go-review.googlesource.com/c/go/+/492375
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Bryan Mills <bcmills@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Bypass: Ian Lance Taylor <iant@google.com>