feat(android): improve initialization scripts implementation

[lucasfernog]

What kind of change does this PR introduce?

• Bugfix
• Feature
• Docs
• New Binding issue #___
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change?

• Yes, and the changes were approved in issue #___
• No

Checklist

• When resolving issues, they are referenced in the PR's title (e.g fix: remove a typo, closes #___, #___)
• A change file is added if any packages will require a version bump due to this PR per the instructions in the readme.
• I have added a convincing reason for adding this feature, if necessary

Other information

Deleted RustWebChromeClient references, it's no longer needed.
The new RustWebViewClient.kt:

package com.tauri.api

import android.graphics.Bitmap
import android.webkit.*

class RustWebViewClient(initScripts: Array<String>): WebViewClient() {
    private val initializationScripts: Array<String>
  
    init {
      initializationScripts = initScripts
    }

    override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
        for (script in initializationScripts) {
          view?.evaluateJavascript(script, null)
        }
        super.onPageStarted(view, url, favicon)
    }
  
    override fun shouldOverrideUrlLoading(view: WebView?, request: WebResourceRequest?): Boolean {
        return false
    }

    override fun shouldInterceptRequest(
        view: WebView,
        request: WebResourceRequest
    ): WebResourceResponse? {
        return handleRequest(request)
    }

    companion object {
        init {
            System.loadLibrary("api")
        }
    }

    private external fun handleRequest(request: WebResourceRequest): WebResourceResponse?
}