Make public additional types from sha1 module [feature] (#11694)

* Make public additional types from sha1 module

After making public newSha1State, update and finalize methods from the
sha1 module was forgotten to be made public Sha1Digest and Sha1State
types used by the new public methods.

* Update changelog.md with sha1 module changes

changelog.md

@@ -19,6 +19,7 @@
 
 - Enable Oid usage in hashtables. (#11472)
 
+- Make public `Sha1Digest` and `Sha1State` types and `newSha1State`, `update` and `finalize` procedures from `sha1` module. (#11694)
 
 ## Language additions
 

lib/std/sha1.nim

@@ -40,11 +40,11 @@ from endians import bigEndian32, bigEndian64
 const Sha1DigestSize = 20
 
 type
-  Sha1Digest = array[0 .. Sha1DigestSize-1, uint8]
+  Sha1Digest* = array[0 .. Sha1DigestSize-1, uint8]
   SecureHash* = distinct Sha1Digest
 
 type
-  Sha1State = object
+  Sha1State* = object
     count: int
     state: array[5, uint32]
     buf:   array[64, byte]