refactor: migrate resource_github_actions_environment_variable to tflog

Replace Go standard `log` package with HashiCorp structured `tflog` for consistent logging across the provider.

Changes:
- Replace `log` import with `fmt` and add `tflog` import
- Convert `log.Printf` to `tflog.Info` with structured fields

Part of #3070

Author: texasich

github/resource_github_actions_environment_variable.go

@@ -3,11 +3,12 @@ package github
 import (
 	"context"
 	"errors"
-	"log"
+	"fmt"
 	"net/http"
 	"net/url"
 
 	"github.com/google/go-github/v85/github"
+	"github.com/hashicorp/terraform-plugin-log/tflog"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/diag"
 	"github.com/hashicorp/terraform-plugin-sdk/v2/helper/schema"
 )
@@ -140,7 +141,9 @@ func resourceGithubActionsEnvironmentVariableRead(ctx context.Context, d *schema
 		var ghErr *github.ErrorResponse
 		if errors.As(err, &ghErr) {
 			if ghErr.Response.StatusCode == http.StatusNotFound {
-				log.Printf("[INFO] Removing actions variable %s from state because it no longer exists in GitHub", d.Id())
+				tflog.Info(ctx, fmt.Sprintf("Removing actions variable %s from state because it no longer exists in GitHub", d.Id()), map[string]any{
+				"variable_id": d.Id(),
+			})
 				d.SetId("")
 				return nil
 			}