[pkg/ottl] Fix OTTL functions by using setters #34882

Job	Run time
arm-unittest-matrix (receiver-3)	6m 5s
arm-unittest-matrix (receiver-0)	6m 22s
arm-unittest-matrix (receiver-1)	8m 17s
arm-unittest-matrix (exporter-3)	5m 24s
arm-unittest-matrix (exporter-0)	4m 12s
arm-unittest-matrix (exporter-2)	4m 32s
arm-unittest-matrix (processor-1)	4m 43s
arm-unittest-matrix (processor-0)	3m 58s
arm-unittest-matrix (extension)	7m 31s
arm-unittest-matrix (exporter-1)	8m 6s
arm-unittest-matrix (cmd-0)	3m 0s
arm-unittest-matrix (other)	5m 1s
arm-unittest-matrix (receiver-2)	9m 54s
arm-unittest-matrix (connector)	4m 46s
arm-unittest-matrix (internal)	7m 2s
arm-unittest-matrix (pkg)	5m 36s
arm-unittest	5s
flakytests-generate-issues	0s
	1h 34m 34s

Provide feedback