Remove variables related to certs and keys

[rileyschuit]

I was brought here via https://exploreembedded.com/wiki/AWS_IOT_with_Arduino_ESP32

Could not compile till aws_root_ca_pem, certificate_pem_crt, and private_pem_key was commented out:
https://github.com/ExploreEmbedded/Hornbill-Examples/blob/master/arduino-esp32/AWS_IOT/src/aws_iot_certficates.c

Receive error (based on what you comment out):
libraries\AWS_IOT\aws_iot_certficates.c.o:(.rodata.aws_root_ca_pem+0x0): multiple definition of aws_root_ca_pem'`

libraries\AWS_IOT\aws_iot_certficates.c.o:(.rodata.certificate_pem_crt+0x0): multiple definition of certificate_pem_crt'`

libraries\AWS_IOT\aws_iot_certficates.c.o:(.rodata.private_pem_key+0x0): multiple definition of private_pem_key'`

[emcfins]

I just had this same issue - you need to move the aws_iot_certificates.c file in AWS_IOT directory to aws_iot_certificates.c.old. I had copied it so there were 2 copies of the same file with the same name, one in my project folder, one in the AWS_IOT directory.
Check to see if you have 2 copies as well. If you do, rename the file in the AWS_IOT directory to aws_iot_certificates.c.old and you should be all set. I was able to compile without errors after I renamed the file.