Sign codedeploy-agent package

In order to install CodeDeploy Agent on Amazon Linux 2 / CentOS / RHEL servers that are configured for the CIS Level 3 Benchmark (High), all packages must be digitally signed by a CA that is recognized by the Operating System. This maps to RHEL STIG Vulnerability V-71979 and Amazon Linux 2 STIG Benchmark 1.2.4.

**Current Value**
```
[ec2-user@ip-172-31-xxx-xxx ~]$ rpm -qi codedeploy-agent
Name : codedeploy-agent
Version : 1.1.2
Release : 1855
Architecture: noarch
Group : Applications/System
Size : 25823745
License : Amazon.com Internal
Signature : (none)
Source RPM : codedeploy-agent-1.1.2-1855.src.rpm
Build Date : Sat Jul 18 00:01:17 2020
Build Host : sds-tod-workers-corp-pdx1-60009.pdx1.corp.amazon.com
Relocations : (not relocatable)
Vendor : Amazon.com
Summary : Provides the required files for CodeDeploy agent to run in EC2 instances
Description :
CodeDeploy instance agent is responsible for doing the actual work of deploying software
on an EC2 instance.
```

**Expected Value (based on SSM Agent)**
```
[ec2-user@ip-172-31-xxx-xxx ~]$ rpm -qi codedeploy-agent
Name : codedeploy-agent
Version : 1.1.2
Release : 1855
Architecture: noarch
Group : Amazon/Tools
License : ASL 2.0
Signature : RSA/SHA256, Tue Aug 4 14:58:37 2020, Key ID 11cf1f95c87f5b1a
Source RPM : codedeploy-agent-1.1.2-1855.src.rpm
Build Date : Sat Jul 18 00:01:17 2020
Build Host : build.amazon.com
Relocations : (not relocatable)
Vendor : Amazon.com
Summary : Provides the required files for CodeDeploy agent to run in EC2 instances
Description :
CodeDeploy instance agent is responsible for doing the actual work of deploying software
on an EC2 instance.
```

Empieza por rastrear cómo se compila y publica el RPM de codedeploy-agent para Amazon Linux 2, CentOS y RHEL. Confirma los metadatos y la firma del paquete con rpm -qi; se considera completado cuando el paquete informa de una firma RSA/SHA256 reconocida en lugar de Signature: (none), utilizando la clave de firma esperada.

Escrito por el modelo de indexación a partir del texto del issue.