这是因为使用reqwest的包，用到了openssl的库。
按照提示"Make sure you also have the development packages of openssl installed.
libssl-dev on Ubuntu or openssl-devel on Fedora.，
执行如下命令
1、 sudo apt install libssl-dev
再次执行cargo run 还是同样报错，再看提示，好像还缺一个包
“It looks like you're compiling on Linux and also targeting Linux. Currently this
requires the pkg-config utility to find OpenSSL but unfortunately pkg-config
could not be found. If you have OpenSSL installed you can likely fix this by
installing pkg-config.“
2、 sudo apt install pkg-config
安装完成后，再执行cargo run 编译通过了。
标签：cargo,run,openssl,报错,pkg,config From： https://www.cnblogs.com/qumogu/p/17015841.html