Adding data-test-subj to super-date-picker (#1782)

* Adding data-test-subj

Adding missing data-test-subj fields to missing objects on the relative tab

* Update CHANGELOG.md

* fixed spacing

* Update CHANGELOG.md

* Update CHANGELOG.md

Co-Authored-By: marius-dr <marius-dr@users.noreply.github.com>

* Fix tabs to spaces

CHANGELOG.md

@@ -1,7 +1,7 @@
 ## [`master`](https://github.com/elastic/eui/tree/master)
 
 - Converted `EuiFormErrorText` to TS ([#1772](https://github.com/elastic/eui/pull/1772))
-
+- Added `data-test-subj`s to `EuiSuperDatePicker`'s `EuiRelativeTab` inputs  ([#1782](https://github.com/elastic/eui/pull/1782))
 **Bug fixes**
 
 - Update ButtonIconColor type to provide all available options ([#1783](https://github.com/elastic/eui/pull/1783))

src/components/date_picker/super_date_picker/date_popover/relative_tab.js

@@ -69,6 +69,7 @@ export class EuiRelativeTab extends Component {
             >
               <EuiFieldNumber
                 aria-label="Count of"
+                data-test-subj={`superDatePickerRelativeDateInputNumber`}
                 value={this.state.count}
                 onChange={this.onCountChange}
                 isInvalid={isInvalid}
@@ -78,6 +79,7 @@ export class EuiRelativeTab extends Component {
           <EuiFlexItem>
             <EuiFormRow>
               <EuiSelect
+                data-test-subj={`superDatePickerRelativeDateInputUnitSelector`}
                 value={this.state.unit}
                 options={relativeOptions}
                 onChange={this.onUnitChange}
@@ -90,6 +92,7 @@ export class EuiRelativeTab extends Component {
         </EuiFormRow>
         <EuiFormRow>
           <EuiSwitch
+            data-test-subj={`superDatePickerRelativeDateRoundSwitch`}
             label={`Round to the ${timeUnits[this.state.unit.substring(0, 1)]}`}
             checked={this.state.round}
             onChange={this.onRoundChange}