Adjust new campaign button wording

Created by: eseliger

Closes https://github.com/sourcegraph/sourcegraph/issues/17481

Created by: sourcegraph-bot

Notifying subscribers in CODENOTIFY files for diff 15afbaf1a1cbf82c88c9cc844d5f7a8699bbde3f...21242e7ab82d203d1af001d377f68421536be9f4.

Notify	File(s)
@LawnGnome	client/web/src/enterprise/campaigns/list/CampaignListPage.tsx

Created by: codecov[bot]

Codecov Report

Merging #17527 (21242e7) into main (15afbaf) will not change coverage. The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main   #17527   +/-   ##
=======================================
  Coverage   51.70%   51.70%           
=======================================
  Files        1717     1717           
  Lines       85366    85366           
  Branches     7608     7608           
=======================================
  Hits        44142    44142           
  Misses      37324    37324           
  Partials     3900     3900           

Flag	Coverage Δ
go	50.65% <ø> (ø)
integration	30.70% <100.00%> (+0.01%)
storybook	30.34% <100.00%> (ø)
typescript	54.26% <100.00%> (ø)
unit	34.67% <0.00%> (ø)

Impacted Files	Coverage Δ
...src/enterprise/campaigns/list/CampaignListPage.tsx	88.00% <100.00%> (ø)