fix(git/log): match sha-256 hashes in syntax

syntax/gitlog.vim

@@ -4,7 +4,7 @@ endif
 
 syntax match gitlogGraph      contained /^[*|\\\/_ ]*/
             \ nextgroup=gitlogHash
-syntax match gitlogHash       contained /\<\x\{7,40\}\>/
+syntax match gitlogHash       contained /\<\x\{7,64\}\>/
             \ nextgroup=gitlogDate skipwhite
 syntax match gitlogDate       contained /\<\d\{4}-\d\{2}-\d\{2}\>/
             \ nextgroup=gitlogAuthor skipwhite
@@ -12,7 +12,7 @@ syntax match gitlogAuthor     contained /{[^}]\+}/
             \ nextgroup=gitlogRef skipwhite
 syntax match gitlogRef        contained /([^)]\+)/
 syntax match gitlogLine
-            \ /^[*|\\\/_ ]*\x\{7,40}\s\+\d\{4}-\d\{2}-\d\{2}\s\+{[^}]\+}.*/
+            \ /^[*|\\\/_ ]*\x\{7,64}\s\+\d\{4}-\d\{2}-\d\{2}\s\+{[^}]\+}.*/
             \ contains=gitlogGraph
 syntax match gitlogGraphLine /^[*|\\\/_ ]\+$/
             \ contains=gitlogGraph