refactor(internal/circonus): Metric filters parsing defaults to v1.20…

…+, checks errors

Refactor metric filters parsing to be simpler and check all errors

issue #CIRC-8497

This change refactors code to be simpler (more easily readable) and
check all errors

* Tags: errors metric filters v1.20+ parse

internal/circonus/metric_filters.go

@@ -140,19 +140,15 @@ func (c *Check) defaultFilters() [][]string {
 
 	var defaultMetricFiltersData []byte
 
-	currversion, err := version.NewVersion(c.clusterVers)
+	v120, err := version.NewVersion(v120str)
 	if err != nil {
-		c.log.Warn().Err(err).Msg("parsing api version")
-		currversion, _ = version.NewVersion(v120str)
+		c.log.Warn().Err(err).Msg("parsing " + v120str)
 	}
 
-	v120, err := version.NewVersion(v120str)
+	currversion, err := version.NewVersion(c.clusterVers)
 	if err != nil {
-		c.log.Warn().Err(err).Msg("parsing" + v120str)
-		return [][]string{
-			{"deny", "^$", "empty"},
-			{"allow", "^.+$", "all"},
-		}
+		c.log.Warn().Err(err).Msg("parsing api version")
+		currversion = v120
 	}
 
 	if currversion.LessThan(v120) {