Don't clear selection when switching tabs

The `store.clearSelection()` call currently clears the selection and also all
other filters, which means that switching tabs changed several things in the UI
beyond just the current tab. Change this so it just changes the tab.

src/sidebar/components/SelectionTabs.tsx

@@ -115,7 +115,6 @@ function SelectionTabs({
   const isWaitingToAnchorAnnotations = store.isWaitingToAnchorAnnotations();
 
   const selectTab = (tabId: TabName) => {
-    store.clearSelection();
     store.selectTab(tabId);
   };
 

src/sidebar/components/test/SelectionTabs-test.js

@@ -40,7 +40,6 @@ describe('SelectionTabs', () => {
       enableExperimentalNewNoteButton: false,
     };
     fakeStore = {
-      clearSelection: sinon.stub(),
       selectTab: sinon.stub(),
       isWaitingToAnchorAnnotations: sinon.stub().returns(false),
       selectedTab: sinon.stub().returns('annotation'),
@@ -295,7 +294,6 @@ describe('SelectionTabs', () => {
 
       findButton(wrapper, label).simulate('click');
 
-      assert.calledOnce(fakeStore.clearSelection);
       assert.calledWith(fakeStore.selectTab, tab);
     });
   });
@@ -306,7 +304,6 @@ describe('SelectionTabs', () => {
 
     findButton(wrapper, 'Page Notes').simulate('click');
 
-    assert.notCalled(fakeStore.clearSelection);
     assert.notCalled(fakeStore.selectTab);
   });