Fix link error: remove unexist link

Signed-off-by: Jiale Zhang <[email protected]>

Author: Jiale Zhang

image-rs/tests/README.md

@@ -31,11 +31,6 @@ encrypt the images. To genetate KBS encrypted image, please refer to the followi
 
 Implemented in `signature_verification.rs`.
 
-Image Signature Verification includes the following four
-tests illustrated in 
-<https://github.com/confidential-containers/image-rs/issues/43>,
-s.t.
-
 | |signed image|unsigned image|
 |---|---|---|
 |protected registry|protected_signed_allow, protected_signed_deny|protected_unsigned_deny|