Removed resizing of vectors from MultiColvarTemplate::performTask #3420

Job	Run time
docker / docker (fedora39)	20m 2s
linux / linux (-doc-mpi-)	40m 48s
docker / docker (rocky8)	23m 37s
codecheck / codecheck	44m 49s
conda / conda (ubuntu-20.04)	12m 5s
linux / linux (-mpi-)	51m 23s
conda / conda (macos-12)	1s
linux / linux (-coverage-mpi-)	1h 1m 54s
conda / conda (macos-14)	1m 50s
linux / linux (-debug-)	47s
mac / macsimple (macos-12)	1s
linux / linux (-debug-mpi-)	40s
mac / macports (macos-12)	1s
mac / macsimple (macos-14)	4m 55s
linux / linux (-intel-)	8m 18s
mac / macports (macos-14)	3m 52s
linux / linux (-pycv-mpi-)	18m 40s
mac / macports (+allmodules, macos-12)	1s
	4h 53m 44s

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