[#12588] Improve test code coverage of core components - ToastComponent

[techMedMau]

Part of #12588

Outline of Solution
Add test cases in src/web/app/components/toast/toast.component.spec.ts

[github-actions]

Hi @techMedMau, thank you for your interest in contributing to TEAMMATES!
However, your PR does not appear to follow our contribution guidelines:

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[cedricongjh]

LGTM, thank you for your contribution!

[domlimm]

Let's add a test for:

/**
   * Returns true if the argument passed is a TemplateRef.
   */
  isTemplate(): boolean {
    if (!this.toast) {
      return false; // done!
    }
    // a test for this too! please and thank you
    return this.toast.message instanceof TemplateRef;
  }

[techMedMau]

Let's add a test for:

/**
   * Returns true if the argument passed is a TemplateRef.
   */
  isTemplate(): boolean {
    if (!this.toast) {
      return false; // done!
    }
    // a test for this too! please and thank you
    return this.toast.message instanceof TemplateRef;
  }

Added

[domlimm]

LGTM!