Fix tests for attestations

Library/Homebrew/attestation.rb

@@ -53,7 +53,6 @@ module Homebrew
       return true if Homebrew::EnvConfig.verify_attestations?
       return false if GitHub::API.credentials.blank?
       return false if ENV.fetch("CI", false)
-      return false unless Formula["gh"].any_version_installed?
 
       Homebrew::EnvConfig.developer? || Homebrew::EnvConfig.devcmdrun?
     end
@@ -70,7 +69,7 @@ module Homebrew
       return @gh_executable if @gh_executable.present?
 
       with_env(HOMEBREW_NO_VERIFY_ATTESTATIONS: "1") do
-        @gh_executable = ensure_executable!("gh")
+        @gh_executable = ensure_executable!("gh", reason: "verifying attestations")
 
         gh_version = Version.new(system_command!(@gh_executable, args: ["--version"], print_stderr: false)
                                  .stdout.match(/\d+(?:\.\d+)+/i).to_s)

Library/Homebrew/cmd/install.rb

@@ -267,7 +267,7 @@ module Homebrew
           if formulae.include?(Formula["gh"])
             formulae.unshift(T.must(formulae.delete(Formula["gh"])))
           else
-            Homebrew::Attestation.ensure_gh_installed!
+            Homebrew::Attestation.gh_executable
           end
         end
 

Library/Homebrew/cmd/reinstall.rb

@@ -128,7 +128,7 @@ module Homebrew
           if formulae.include?(Formula["gh"])
             formulae.unshift(T.must(formulae.delete(Formula["gh"])))
           else
-            Homebrew::Attestation.ensure_gh_installed!
+            Homebrew::Attestation.gh_executable
           end
         end
 

Library/Homebrew/cmd/upgrade.rb

@@ -138,7 +138,7 @@ module Homebrew
           if formulae.include?(Formula["gh"])
             formulae.unshift(formulae.delete(Formula["gh"]))
           else
-            Homebrew::Attestation.ensure_gh_installed!
+            Homebrew::Attestation.gh_executable
           end
         end
 

Library/Homebrew/test/attestation_spec.rb

@@ -77,7 +77,7 @@ RSpec.describe Homebrew::Attestation do
 
     it "calls ensure_executable and ensure_formula_installed" do
       expect(described_class).to receive(:ensure_executable!)
-        .with("gh")
+        .with("gh", reason: "verifying attestations")
         .and_return(fake_old_gh)
 
       expect(described_class).to receive(:ensure_formula_installed!)