Adapt all scripts to yescrypt (#216)

* Revert "fix: clean obsolete check 99.5.4.5.1, now handled by 5.3.4 (#215)"

This reverts commit 670c8c62f5.

We still want to verify the preexisting hashes in /etc/shadow,
even if the PAM configuration is correct for new passwords (5.3.4).

* Adapt 5.3.4, 99.5.4.5.1 and 99.5.4.5.2 to yescrypt

tests/launch_tests.sh

@@ -140,6 +140,11 @@ _run() {
     echo $? >"$outdir/$usecase_name.retval"
     ret=$(<"$outdir"/"$usecase_name".retval)
     get_stdout
+    if [ -s "$outdir/${usecase_name}_err.log" ]; then
+        echo ">>> stderr follows"
+        cat "$outdir/${usecase_name}_err.log"
+        echo "<<< end of stderr"
+    fi
 }
 
 # Load assertion functions for functionnal tests