Revert "add a discard button"

This reverts commit 0079afa.

src/fragmentarium/ui/fragment/ArchaeologyEditor.tsx

@@ -12,7 +12,6 @@ import { ArchaeologyDto } from 'fragmentarium/domain/archaeologyDtos'
 import { Fragment } from 'fragmentarium/domain/fragment'
 import withData from 'http/withData'
 import { FindspotService } from 'fragmentarium/application/FindspotService'
-import './ArchaeologyEditor.sass'
 
 interface Props {
   archaeology?: Archaeology
@@ -48,7 +47,7 @@ interface FindspotOption {
 
 class ArchaeologyEditor extends Component<Props, State> {
   private isDirty = false
-  private originalState: Readonly<State>
+  private originalState: State
   private updateArchaeology: (archaeology: ArchaeologyDto) => Promise<Fragment>
   private findspotsById: ReadonlyMap<number, Findspot>
   private findspots: readonly Findspot[]
@@ -137,12 +136,6 @@ class ArchaeologyEditor extends Component<Props, State> {
     }
   }
 
-  reset = (event: React.MouseEvent<HTMLElement>): void => {
-    this.isDirty = false
-    this.setState(this.originalState)
-    event.currentTarget.blur()
-  }
-
   submit = (event: FormEvent<HTMLElement>): void => {
     event.preventDefault()
 
@@ -230,18 +223,10 @@ class ArchaeologyEditor extends Component<Props, State> {
         <Form.Row>{this.renderExcavationSiteForm()}</Form.Row>
         <Form.Row>{this.renderIsRegularExcavationForm()}</Form.Row>
         <Form.Row>{this.renderFindspotForm()}</Form.Row>
-        <Button
-          variant="danger"
-          disabled={this.props.disabled || !this.isDirty}
-          onClick={this.reset}
-        >
-          Discard
-        </Button>
         <Button
           variant="primary"
           type="submit"
           disabled={this.props.disabled || !this.isDirty}
-          className={'submit-button'}
         >
           Save
         </Button>