chore: Remove unused field

src/main/java/de/mlessmann/certassist/openssl/CertificateRequest.java

@@ -8,10 +8,6 @@ import lombok.Data;
 @Builder
 public class CertificateRequest {
 
-    @Builder.Default
-    @Deprecated
-    private String oid = UUID.randomUUID().toString();
-
     private RequestType type;
     private String commonName;
     private String trustingAuthority;