Replace deprecated ioutil with io and os (#20776)

* Replace ioutil with io and os

* Replace ioutil in utils/file.go

* Minor fix to tests and excluded files

Co-authored-by: Tim Scheuermann <tim.scheuermann@mattermost.com>
Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

api4/cloud.go

@@ -7,7 +7,7 @@ import (
 	"bytes"
 	"encoding/binary"
 	"encoding/json"
-	"io/ioutil"
+	"io"
 	"net/http"
 	"time"
 
@@ -123,7 +123,7 @@ func changeSubscription(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.changeSubscription", "api.cloud.app_error", nil, err.Error(), http.StatusBadRequest)
 		return
@@ -174,7 +174,7 @@ func requestCloudTrial(c *Context, w http.ResponseWriter, r *http.Request) {
 	}
 
 	// check if the email needs to be set
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.requestCloudTrial", "api.cloud.app_error", nil, err.Error(), http.StatusInternalServerError)
 		return
@@ -221,7 +221,7 @@ func validateBusinessEmail(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.requestCloudTrial", "api.cloud.app_error", nil, err.Error(), http.StatusInternalServerError)
 		return
@@ -394,7 +394,7 @@ func updateCloudCustomer(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.updateCloudCustomer", "api.cloud.app_error", nil, err.Error(), http.StatusInternalServerError)
 		return
@@ -432,7 +432,7 @@ func updateCloudCustomerAddress(c *Context, w http.ResponseWriter, r *http.Reque
 		return
 	}
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.updateCloudCustomerAddress", "api.cloud.app_error", nil, err.Error(), http.StatusInternalServerError)
 		return
@@ -504,7 +504,7 @@ func confirmCustomerPayment(c *Context, w http.ResponseWriter, r *http.Request)
 	auditRec := c.MakeAuditRecord("confirmCustomerPayment", audit.Fail)
 	defer c.LogAuditRec(auditRec)
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.confirmCustomerPayment", "api.cloud.app_error", nil, err.Error(), http.StatusInternalServerError)
 		return
@@ -594,7 +594,7 @@ func handleCWSWebhook(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	bodyBytes, err := ioutil.ReadAll(r.Body)
+	bodyBytes, err := io.ReadAll(r.Body)
 	if err != nil {
 		c.Err = model.NewAppError("Api4.handleCWSWebhook", "api.cloud.app_error", nil, err.Error(), http.StatusInternalServerError)
 		return