Remove support for reading CAS files from disk in spec helpers

We never use this feature so it is just dead code and if we would ever
want to do it it would be trivial to code.

Author: jeltz

spec/helpers.rb

@@ -355,7 +355,6 @@ def next_serial
 		end
 
 		def create_ca_cert(name, ca_key, x509_name, valid_years: 10)
-			ca_key = OpenSSL::PKey::RSA.new File.read "#{ca_key}" unless ca_key.kind_of?(OpenSSL::PKey::RSA)
 			ca_name = OpenSSL::X509::Name.parse x509_name
 
 			ca_cert = OpenSSL::X509::Certificate.new
@@ -396,7 +395,6 @@ def create_key(name, rsa_size: 2048)
 		end
 
 		def create_signing_request(name, x509_name, key)
-			key = OpenSSL::PKey::RSA.new File.read "#{key}" unless key.kind_of?(OpenSSL::PKey::RSA)
 			csr = OpenSSL::X509::Request.new
 			csr.version = 0
 			csr.subject = OpenSSL::X509::Name.parse x509_name
@@ -411,9 +409,6 @@ def create_signing_request(name, x509_name, key)
 		end
 
 		def create_cert_from_csr(name, csr, ca_cert, ca_key, valid_years: 10, dns_names: nil)
-			ca_key = OpenSSL::PKey::RSA.new File.read "#{ca_key}" unless ca_key.kind_of?(OpenSSL::PKey::RSA)
-			ca_cert = OpenSSL::X509::Certificate.new File.read "#{ca_cert}" unless ca_cert.kind_of?(OpenSSL::X509::Certificate)
-			csr = OpenSSL::X509::Request.new File.read "#{csr}" unless csr.kind_of?(OpenSSL::X509::Request)
 			raise 'CSR can not be verified' unless csr.verify csr.public_key
 
 			csr_cert = OpenSSL::X509::Certificate.new