Add `Help Request Table` component to Storybook (along with fixtures)

[x] There is a 'helpRequestFixtures.js' file in the 'src/fixtures' directory that exports an array with at least one object element representing the a single entry in the table, and another element representing multiple elements in the table.
[x] There is a 'HelpRequestTable.stories.js' and a 'HelpRequestForm.stories.js' file in 'src/stories/components/HelpRequest'.
[x] 'HelpRequestTable.stories.js' exports 4 instances of HelpRequestTable component exported for each of the following: empty (no entries), single entry, three entries, three entries as an admin.
[x] 'HelpRequestForm.stories.js' exports a HelpRequestForm component for creating an entry, and one for updating an entry.
[x] Both stories show up in Storybook.

ucsb-cs156-f22 / team03-f22-6pm-3