Flag iOS 9.0 deprecation warnings

# Bug Report

## Problem

### What is expected to happen?

Not to see deprecation warnings for iOS 9.0

### What does actually happen?

The following deprecation warnings appear in my log when building my Cordova app on [monaca.io](https://monaca.io/).

`stringByAddingPercentEscapesUsingEncoding` is deprecated: first deprecated in iOS 9.0

- Use `stringByAddingPercentEncodingWithAllowedCharacters`: instead, which always uses the recommended UTF-8 encoding, and which encodes for a specific URL component or subcomponent since each URL component or subcomponent has different rules for what characters are valid.
- [`CDVLocalFilesystem.m:128:43`](https://github.com/apache/cordova-plugin-file/blob/master/src/ios/CDVLocalFilesystem.m#L128)
- [`CDVFile.m:590:25`](https://github.com/apache/cordova-plugin-file/blob/master/src/ios/CDVFile.m#L590)

`stringByReplacingPercentEscapesUsingEncoding` is deprecated: first deprecated in iOS 9.0

- Use `stringByRemovingPercentEncoding` instead, which always uses the recommended UTF-8 encoding.
- [`CDVFile.m:589:35`](https://github.com/apache/cordova-plugin-file/blob/master/src/ios/CDVFile.m#L589)

## Information

Apple docs: https://developer.apple.com/documentation/foundation/nsstring/1407783-stringbyreplacingpercentescapesu

### Command or Code

Forgive me if this is the wrong command - I'm extracting it from the log Monaca automatically generates.

```
CompileC /Users/builder/Library/Developer/Xcode/DerivedData/Assess-dlavgjwbqzsbhgafcbkmwzzohbxe/Build/Intermediates.noindex/ArchiveIntermediates/Assess/IntermediateBuildFilesPath/Assess.build/Release-iphoneos/Assess.build/Objects-normal/arm64/CDVLocalFilesystem.o /tmp/download/platforms/ios/Assess/Plugins/cordova-plugin-file/CDVLocalFilesystem.m
```

### Environment, Platform, Device

iOS (also present in OSX)

### Version information

Cordova: 12
Cordova iOS: 7.1.0
Cordova Plugin File: 8.1.0
Xcode: 15.0.1

## Checklist

- [x] I searched for existing GitHub issues
- [x] I updated all Cordova tooling to most recent version
- [x] I included all the necessary information above

Inspect src/ios/CDVLocalFilesystem.m at line 128 and src/ios/CDVFile.m at lines 589-590, then compare the reported deprecated NSString calls with Apple's documented replacements. Done means the iOS and macOS builds no longer emit the iOS 9.0 deprecation warnings for these calls.

Written by the indexing model from the issue text.