feat: add OpenBao plugin RPMs for consul and nomad secrets engines

- Add openbao-plugin-secret-consul v0.1.0 RPM configuration
- Add openbao-plugin-secret-nomad v0.1.4 RPM configuration
- Add openbao-plugins v1.0.0 meta package that installs both plugins
- Plugins install to /opt/openbao-plugins directory
- Include pre-install scripts to create plugin directory
- Support for EL8 and EL9 distributions

rpms/openbao-plugin-secret-nomad/resources/build.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/bash
+
+# Download the required files
+curl -L -o /app/openbao-plugin-secrets-nomad.tar.gz https://github.com/openbao/openbao-plugins/releases/download/secrets-nomad-v${PACKAGE_VERSION}/openbao-plugin-secrets-nomad_linux_amd64_v1.tar.gz
+
+# Extract the binary
+tar -xzf /app/openbao-plugin-secrets-nomad.tar.gz -C /app
+
+# Rename the binary to a simpler name
+mv /app/openbao-plugin-secrets-nomad_linux_amd64_v1 /app/openbao-plugin-secrets-nomad
+
+# Make the binary executable
+chmod +x /app/openbao-plugin-secrets-nomad
+
+# Build the RPM
+nfpm pkg --config /app/resources/nfpm.yaml --target /app/dist --packager rpm