install missing modules.
PCRE not need download source, just install below modules. especilly libpcre++-dev,
I think libpcre2-dev is enough, but the nginx need c++ wrapper, so libpcre++-dev also needed.
sudo apt-get install libpcre2-dev
sudo apt-get install pcre2-utilssudo apt-get install libpcre++-dev
sudo apt-get install libssh-dev
change user to the ubuntu user in nginx.conf.