Fix Fedora sentinelone instructions

Why is this change being made?

These instructions resulted in the following error for me:

$ sudo -E rpm -i --nodigest SentinelAgent_linux_v22_4_2_4.rpm S1_AGENT_INSTALL_CONFIG_PATH="$(pwd)/config.cfg"
error: open of S1_AGENT_INSTALL_CONFIG_PATH=/home/mk/Downloads/sentinelone/config.cfg failed: No such file or directory

We already export this env var in the previous step, so there is no need to set it again. Also, env vars should be set before invoking a shell program; setting it at the end will make it be interpreted as a CLI argument to rpm IIUC.

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