Chore: use Array.isArray rather than lodash (#27898)

packages/grafana-data/src/dataframe/MutableDataFrame.ts

 import { Field, DataFrame, DataFrameDTO, FieldDTO, FieldType } from '../types/dataFrame';
 import { KeyValue, QueryResultMeta } from '../types/data';
 import { guessFieldTypeFromValue, guessFieldTypeForField, toDataFrameDTO } from './processDataFrame';
-import isArray from 'lodash/isArray';
 import isString from 'lodash/isString';
 import { makeFieldParser } from '../utils/fieldParser';
 import { MutableVector, Vector } from '../types/vector';
@@ -79,7 +78,7 @@ export class MutableDataFrame<T = any> extends FunctionalVector<T> implements Da
     let buffer: any[] | undefined = undefined;
 
     if (f.values) {
-      if (isArray(f.values)) {
+      if (Array.isArray(f.values)) {
         buffer = f.values as any[];
       } else {
         buffer = (f.values as Vector).toArray();

packages/grafana-ui/src/components/StatsPicker/StatsPicker.tsx

 import React, { PureComponent } from 'react';
 
-import isArray from 'lodash/isArray';
 import difference from 'lodash/difference';
 
 import { Select } from '../Select/Select';
@@ -55,7 +54,7 @@ export class StatsPicker extends PureComponent<Props> {
 
   onSelectionChange = (item: SelectableValue<string>) => {
     const { onChange } = this.props;
-    if (isArray(item)) {
+    if (Array.isArray(item)) {
       onChange(item.map(v => v.value));
     } else {
       onChange(item && item.value ? [item.value] : []);