Remove center render prop from PageHeader

Only one instance of use, not worth the added complexity

ui/src/shared/components/PageHeader.tsx

@@ -7,7 +7,6 @@ import SourceIndicator from 'src/shared/components/SourceIndicator'
 interface Props {
   title?: string
   renderTitle?: () => ReactElement<any>
-  renderCenter?: () => ReactElement<any>
   renderOptions?: () => ReactElement<any>
   fullWidth?: boolean
   sourceIndicator?: boolean
@@ -26,7 +25,6 @@ class PageHeader extends Component<Props> {
       <div className={this.className}>
         <div className="page-header--container">
           <div className="page-header--left">{this.renderLeft}</div>
-          {this.renderCenter}
           <div className="page-header--right">
             {this.sourceIndicator}
             {this.renderRight}
@@ -60,14 +58,6 @@ class PageHeader extends Component<Props> {
     return renderTitle()
   }
 
-  private get renderCenter(): JSX.Element {
-    const {renderCenter} = this.props
-
-    if (renderCenter) {
-      return <div className="page-header--center">{renderCenter()}</div>
-    }
-  }
-
   private get renderRight(): JSX.Element {
     const {renderOptions} = this.props
 

ui/src/style/layout/page-header.scss

@@ -21,8 +21,6 @@ $page-header-weight: 400 !important;
 }
 
 .page-header--container {
-  position: relative;
-  width: 100%;
   display: flex;
   align-items: center;
   justify-content: space-between;
@@ -38,7 +36,6 @@ $page-header-weight: 400 !important;
 
 // Left, Center, and Right pieces of the page header
 .page-header--left,
-.page-header--center,
 .page-header--right {
   display: flex;
   align-items: center;
@@ -59,12 +56,6 @@ $page-header-weight: 400 !important;
     }
   }
 }
-.page-header--center {
-  position: absolute;
-  top: 50%;
-  left: 50%;
-  transform: translate(-50%, -50%);
-}
 
 // Intended to be a <h1>
 .page-header--title {