fix: check position index before updating CIS ruleset rule (IBM-Cloud#6472)

* fix: check position index before updating CIS ruleset rule

Signed-off-by: Sirija Reddy <[email protected]>

* fix: check position index before updating CIS ruleset rule

Signed-off-by: Sirija Reddy <[email protected]>

* add MaxItems

---------

Signed-off-by: Sirija Reddy <[email protected]>

Author: sirijaibm

ibm/service/cis/resource_ibm_cis_ruleset_rule.go

@@ -333,6 +333,7 @@ func ResourceIBMCISRulesetRule() *schema.Resource {
 				Type:        schema.TypeList,
 				Optional:    true,
 				Description: "Rules of the rulesets",
+				MaxItems:    1,
 				Elem:        CISRulesetsRulesObject,
 			},
 		},
@@ -521,11 +522,13 @@ func ResourceIBMCISRulesetRuleUpdate(d *schema.ResourceData, meta interface{}) e
 		opt.SetEnabled(rulesetsRuleObject[CISRulesetsRuleActionEnabled].(bool))
 		opt.SetExpression(rulesetsRuleObject[CISRulesetsRuleExpression].(string))
 		opt.SetRef(rulesetsRuleObject[CISRulesetsRuleRef].(string))
-		position, positionError := expandCISRulesetsRulesPositions(rulesetsRuleObject[CISRulesetsRulePosition])
-		if positionError != nil {
-			return flex.FmtErrorf("[ERROR] Error while updating the zone Ruleset %s", err)
+		if d.HasChange(CISRulesetsRule + ".0." + CISRulesetsRulePosition) {
+			position, positionError := expandCISRulesetsRulesPositions(rulesetsRuleObject[CISRulesetsRulePosition])
+			if positionError != nil {
+				return flex.FmtErrorf("[ERROR] Error while updating the zone Ruleset %s", positionError)
+			}
+			opt.SetPosition(&position)
 		}
-		opt.SetPosition(&position)
 
 		if v, ok := rulesetsRuleObject[CISRulesetsRuleRateLimit]; ok && v != nil {
 			ratelimit, ratelimitErr := expandCISRulesetsRulesRateLimits(v)