Remove unnecessary :must_be matcher

It was causing warnings, and we don't need it.

Author: liveh2o

specs/spec_helper.rb

@@ -11,7 +11,6 @@
 require "minitest/autorun"
 require "minitest/pride"
 require "support/minitest_shared"
-require "support/minitest_matchers"
 require "support/schema_statement_examples"
 require "support/view_examples"
 

specs/spectacles/view_spec.rb

@@ -2,6 +2,6 @@
 
 describe Spectacles::View do
   it "is an abstract class" do
-    _(Spectacles::View.abstract_class?).must_be true
+    _(Spectacles::View.abstract_class?).must_equal true
   end
 end

specs/support/minitest_matchers.rb

@@ -16,12 +16,12 @@
       let(:new_product_user) { NewProductUser.duck_lovers.load.first }
 
       it "can have scopes" do
-        _(new_product_user.username).must_be @john.first_name
+        _(new_product_user.username).must_equal @john.first_name
       end
 
       describe "an instance" do
         it "is readonly" do
-          _(new_product_user.readonly?).must_be true
+          _(new_product_user.readonly?).must_equal true
         end
       end
     end
@@ -47,11 +47,11 @@ class MaterializedProductUser < Spectacles::MaterializedView
       end
 
       it "can have scopes" do
-        _(MaterializedProductUser.duck_lovers.load.first.username).must_be @john.first_name
+        _(MaterializedProductUser.duck_lovers.load.first.username).must_equal @john.first_name
       end
 
       it "is readonly" do
-        _(MaterializedProductUser.first.readonly?).must_be true
+        _(MaterializedProductUser.first.readonly?).must_equal true
       end
     end
   end