Custom SSL cert creation fails if ~/.ssh directory doesn't exist

[jnebeker]

Came across this when setting up @jkim628's local dev environment. She had not generated a ssh keypair yet so she had no ~/.ssh directory which caused the creation of the custom SSL cert to fail:

radius-cli/lib/radius/cli/puma_dev.rb

Line 133 in 3176b3a

@combined_cert = Pathname("~/.ssh/pumadev.pem").expand_path

radius-cli/lib/radius/cli/puma_dev.rb

Lines 145 to 149 in 3176b3a

	File.open(combined_cert, "w") do |cert_file|
	cert_file.write base_cert.read
	cert_file.write "\n"
	cert_file.write cert.read
	end

here was the error we were getting:

Configuring SSL...
Creating custom CA SSL cert for puma-dev...
Traceback (most recent call last):
    2: from bin/puma-dev-conf:100:in `<main>'
    1: from bin/puma-dev-conf:100:in `open'
bin/puma-dev-conf:100:in `initialize': No such file or directory @ rb_sysopen - /Users/julianakim/.ssh/pumadev.pem (Errno::ENOENT)

Once we ran ssh-keygen and the ~/.ssh directory was created everything was fine, but it would be nice to catch this edge case and spit out a helpful error message.