LinkerHelper sometimes reads outdated cache

The LinkerHelper class reads libraries, but sometimes the cache is out of date.

From the CentOS_7 build image:

[root@22114a6eeb4c /]# ldconfig -p|grep ssl
        libssl3.so (libc6,x86-64) => /lib64/libssl3.so
        libssl.so.10 (libc6,x86-64) => /lib64/libssl.so.10
[root@22114a6eeb4c /]# ldconfig
[root@22114a6eeb4c /]# ldconfig -p|grep ssl
        libssl3.so (libc6,x86-64) => /lib64/libssl3.so
        libssl.so.10 (libc6,x86-64) => /lib64/libssl.so.10
        libssl.so (libc6,x86-64) => /lib64/libssl.so

This needs to be resolved in the Omnibus Builder to ensure that ldconfig is always using a fresh cache.