fix: use correct path to emulator executable

[edusperoni]

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What is the current behavior?

We're checking for the sdk/tools/android instead of sdk/emulator/emulator/

What is the new behavior?

We check for sdk/emulator/emulator

[rigor789]

lgtm - wondering if this changed with recent sdks, or has this always been there? 🤔

edit: this covers it

nativescript-cli/lib/common/mobile/android/android-virtual-device-service.ts

Lines 119 to 121 in 7ee8455

	// Check https://developer.android.com/studio/releases/sdk-tools.html (25.3.0)
	// Since this version of SDK tools, the emulator is a separate package.
	// However the emulator executable still exists in the "tools" dir.