Remove deprecated destroy API

Fixes #1371

src/Terminal.ts

@@ -290,13 +290,6 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
     }
   }
 
-  /**
-   * @deprecated Use dispose instead.
-   */
-  public destroy(): void {
-    this.dispose();
-  }
-
   private _setup(): void {
     Object.keys(DEFAULT_OPTIONS).forEach((key) => {
       if (this.options[key] === null || this.options[key] === undefined) {

src/TestUtils.test.ts

@@ -99,9 +99,6 @@ export class MockTerminal implements ITerminal {
   dispose(): void {
     throw new Error('Method not implemented.');
   }
-  destroy(): void {
-    throw new Error('Method not implemented.');
-  }
   scrollPages(pageCount: number): void {
     throw new Error('Method not implemented.');
   }

src/Types.ts

@@ -257,7 +257,6 @@ export interface IPublicTerminal extends IDisposable, IEventEmitter {
   selectAll(): void;
   selectLines(start: number, end: number): void;
   dispose(): void;
-  destroy(): void;
   scrollLines(amount: number): void;
   scrollPages(pageCount: number): void;
   scrollToTop(): void;

src/public/Terminal.ts

@@ -121,9 +121,6 @@ export class Terminal implements ITerminalApi {
     this._addonManager.dispose();
     this._core.dispose();
   }
-  public destroy(): void {
-    this._core.destroy();
-  }
   public scrollLines(amount: number): void {
     this._core.scrollLines(amount);
   }