Fix compilation error in StrIntUtilsNoStrictAliasing.cpp
Compile StrIntUtilsNoStrictAliasing.cpp with -O2 instead of -O3

Compiling with -O3 causes segfaults on RHEL 6.
Revert "Temporarily run RPM packaging test container with --privileged so that gdb works."

This reverts commit 32d56374cb2b40b1945c6968eef2f76a2f738bdf.
Upgrade passenger_rpm_packaging