Update application link to filter-repo

The documentation now recommends git filter-repo. In-application help
links should be consistent.

app/helpers/projects_helper.rb

@@ -284,8 +284,8 @@ module ProjectsHelper
     "xcode://clone?repo=#{CGI.escape(default_url_to_repo(project))}"
   end
 
-  def link_to_bfg
-    link_to 'BFG', 'https://rtyley.github.io/bfg-repo-cleaner/', target: '_blank', rel: 'noopener noreferrer'
+  def link_to_filter_repo
+    link_to 'git filter-repo', 'https://github.com/newren/git-filter-repo', target: '_blank', rel: 'noopener noreferrer'
   end
 
   def explore_projects_tab?

app/views/projects/cleanup/_show.html.haml

@@ -6,7 +6,7 @@
     %button.btn.js-settings-toggle
       = expanded ? _('Collapse') : _('Expand')
     %p
-      = _("Clean up after running %{bfg} on the repository" % { bfg: link_to_bfg }).html_safe
+      = _("Clean up after running %{filter_repo} on the repository" % { filter_repo: link_to_filter_repo }).html_safe
       = link_to icon('question-circle'),
           help_page_path('user/project/repository/reducing_the_repo_size_using_git.md'),
           target: '_blank', rel: 'noopener noreferrer'

spec/helpers/projects_helper_spec.rb

@@ -685,11 +685,11 @@ describe ProjectsHelper do
     end
   end
 
-  describe 'link_to_bfg' do
-    subject { helper.link_to_bfg }
+  describe 'link_to_filter_repo' do
+    subject { helper.link_to_filter_repo }
 
-    it 'generates a hardcoded link to the BFG Repo-Cleaner' do
-      result = helper.link_to_bfg
+    it 'generates a hardcoded link to git filter-repo' do
+      result = helper.link_to_filter_repo
       doc = Nokogiri::HTML.fragment(result)
 
       expect(doc.children.size).to eq(1)
@@ -702,8 +702,8 @@ describe ProjectsHelper do
         expect(link.name).to eq('a')
         expect(link[:target]).to eq('_blank')
         expect(link[:rel]).to eq('noopener noreferrer')
-        expect(link[:href]).to eq('https://rtyley.github.io/bfg-repo-cleaner/')
-        expect(link.inner_html).to eq('BFG')
+        expect(link[:href]).to eq('https://github.com/newren/git-filter-repo')
+        expect(link.inner_html).to eq('git filter-repo')
 
         expect(result).to be_html_safe
       end