cirrus.yml: replace py38-pip with py39-pip

Reported-by: Jay Satiro
Fixes #9201
Closes #9202

.cirrus.yml

@@ -42,7 +42,7 @@ freebsd_task:
 
   pkginstall_script:
     - pkg update -f
-    - pkg install -y autoconf automake libtool pkgconf brotli openldap24-client heimdal libpsl libssh2 openssh-portable libidn2 librtmp libnghttp2 nghttp2 stunnel py38-pip
+    - pkg install -y autoconf automake libtool pkgconf brotli openldap24-client heimdal libpsl libssh2 openssh-portable libidn2 librtmp libnghttp2 nghttp2 stunnel py39-pip
     - pkg delete -y curl
     - pip install "cryptography<3.2"
     - pip install "pyOpenSSL<20.0"