Fix part of oppia#19570: Making headers of stats table in contributor admin dashboard more meaningful (oppia#19754)

* changed headers in user stats in contributor admin dashboard.

* added dynamic header for each tab

Author: masterboy376

core/templates/pages/contributor-dashboard-admin-page/contributor-dashboard-tables/contributor-admin-stats-table.component.html

@@ -34,22 +34,22 @@ <h2>{{ noDataMessage }}</h2>
          *ngIf="!loadingMessage && !noDataMessage">
 
     <ng-container matColumnDef="contributorName">
-      <th mat-header-cell *matHeaderCellDef class="user-header"><b> User </b></th>
+      <th mat-header-cell *matHeaderCellDef class="user-header"><b> {{ this.inputs.activeTab }} </b></th>
       <td mat-cell *matCellDef="let element" class="user-value">
-        <span class="mobile-label">User:</span>
+        <span class="mobile-label">{{ this.inputs.activeTab }}:</span>
         <b> {{ element.contributorName }} </b>
       </td>
     </ng-container>
 
     <ng-container matColumnDef="recentPerformance">
       <th mat-header-cell *matHeaderCellDef>
         <b>
-          Performance
+          Recent Performance
           <i class="fas fa-info-circle" matTooltip="Performance is calculated based on the review results of the last 100 accepted/rejected contributions."></i>
         </b>
       </th>
       <td mat-cell *matCellDef="let element">
-        <span class="mobile-label">Performance
+        <span class="mobile-label">Recent Performance
           <i class="fas fa-info-circle" matTooltip="Performance is calculated based on the review results of the last 100 accepted/rejected contributions." #performanceTooltip="matTooltip" (click)="performanceTooltip.toggle()">
           </i>:
         </span>
@@ -60,14 +60,14 @@ <h2>{{ noDataMessage }}</h2>
     <ng-container matColumnDef="overallAccuracy">
       <th mat-header-cell *matHeaderCellDef>
         <b>
-          Accuracy
+          Overall Accuracy
           <i class="fas fa-info-circle"
             matTooltip="Accuracy is based on the ratio of accepted to submitted translations.">
           </i>
         </b>
       </th>
       <td mat-cell *matCellDef="let element">
-        <span class="mobile-label">Accuracy
+        <span class="mobile-label">Overall Accuracy
           <i class="fas fa-info-circle"
             matTooltip="Accuracy is based on the ratio of accepted to submitted translations." #accuracyTooltip="matTooltip" (click)="accuracyTooltip.toggle()">
           </i>: