$ sudo dpkg -i linux-headers-5.2.0-050200rc6-generic_5.2.0-050200rc6.201906222033_amd64.deb

[sudo] password for donz:(Reading database ... 275206 files and directories currently installed.)
Preparing to unpack linux-headers-5.2.0-050200rc6-generic_5.2.0-050200rc6.201906222033_amd64.deb ...

Unpacking linux-headers-5.2.0-050200rc6-generic (5.2.0-050200rc6.201906222033) over (5.2.0-050200rc6.201906222033) ...

dpkg: dependency problems prevent configuration of linux-headers-5.2.0-050200rc6-generic:
 linux-headers-5.2.0-050200rc6-generic depends on libssl1.1 (>= 1.1.0); however:
  Package libssl1.1 is not installed.

dpkg: error processing package linux-headers-5.2.0-050200rc6-generic (--install):dependency problems - leaving unconfigured Errors were encountered while processing: linux-headers-5.2.0-050200rc6-generic