netperfmeter: fix: restore sim-time-limit dropped by an incorrect lint fix

Commit 2a558fb ("fix: minor lint fixes") removed the line

    sim-time-limit = 3600s 1ms

from netperfmeter's [General] section, treating it as a redundant duplicate
of the earlier "sim-time-limit = 100s" on the assumption that the first
assignment wins. For a section-level ini key OMNeT++ uses the LAST assignment,
so 3600s was in fact the effective limit and 100s was the no-op. Removing it
silently cut every netperfmeter run to 100s, which stops the NetPerfMeter app
before its ~600s measurement window completes, so it no longer records its
per-connection summary scalars and the TraceFile-{Sctp,Tcp,Udp} statistical
tests fail.

Restore the effective limit as a single clean line. All four netperfmeter
configs pass again against the existing baselines; SCTP-with-OLIA keeps its
own 30s override.

Author: avarga

examples/inet/netperfmeter/omnetpp.ini

@@ -16,7 +16,7 @@
 
 [General]
 network             = testNetwork
-sim-time-limit      = 100s
+sim-time-limit      = 3600s 1ms
 rng-class           = cMersenneTwister
 seed-0-mt           = 1
 simtime-resolution  = 10ns