Fixed Issues in Livy

Review the list of Livy issues that are resolved in Cloudera Runtime 7.1.7 SP2.

CDPD-47315: Fix channel encryption of multiple interactive Livy sessions on FIPS enabled cluster.

CDPD-39575: Unclosed EventLoopGroup might lead to leak of file descriptors.

CDPD-34010: Add CSP, HSTS security headers to Livy UI.