refactor: rename variable for clarity

test.ts

@@ -198,13 +198,13 @@ export const runTerraformApply = async <TVars extends TerraformVariables>(
 ): Promise<TerraformState> => {
   const stateFile = `${dir}/${crypto.randomUUID()}.tfstate`;
 
-  const combinedEnv: Record<string, string | undefined> = {
+  const childEnv: Record<string, string | undefined> = {
     ...process.env,
     ...(customEnv ?? {}),
   };
   for (const [key, value] of Object.entries(vars) as [string, JsonValue][]) {
     if (value !== null) {
-      combinedEnv[`TF_VAR_${key}`] = String(value);
+      childEnv[`TF_VAR_${key}`] = String(value);
     }
   }
 
@@ -221,7 +221,7 @@ export const runTerraformApply = async <TVars extends TerraformVariables>(
     ],
     {
       cwd: dir,
-      env: combinedEnv,
+      env: childEnv,
       stderr: "pipe",
       stdout: "pipe",
     },