fix filepath when using path input

src/create-pull-request.ts

@@ -1,5 +1,4 @@
 import * as core from '@actions/core'
-import * as fs from 'fs'
 import {graphql} from '@octokit/graphql'
 import type {
   Repository,
@@ -327,7 +326,7 @@ export async function createPullRequest(inputs: Inputs): Promise<void> {
           core.debug(`Reading contents of file: '${file}'`)
           fileChanges.additions!.push({
             path: file,
-            contents: fs.readFileSync(file).toString('base64')
+            contents: utils.readFileBase64([repoPath, file])
           })
         }
 

src/utils.ts

@@ -126,6 +126,10 @@ export function readFile(path: string): string {
   return fs.readFileSync(path, 'utf-8')
 }
 
+export function readFileBase64(pathParts: string[]): string {
+  return fs.readFileSync(path.resolve(...pathParts)).toString('base64')
+}
+
 /* eslint-disable  @typescript-eslint/no-explicit-any */
 function hasErrorCode(error: any): error is {code: string} {
   return typeof (error && error.code) === 'string'