Update failing tests following rebase

Author: Alfred Mazimbe

maven/lib/dependabot/maven/version.rb

@@ -41,6 +41,8 @@ def self.correct?(version)
 
       sig { override.params(version: VersionParameter).void }
       def initialize(version)
+        raise BadRequirementError, "Malformed version string - string is nil" if version.nil?
+
         @version_string = T.let(version.to_s, String)
         @token_bucket = T.let(Dependabot::Maven::VersionParser.parse(version_string), Dependabot::Maven::TokenBucket)
       end

maven/spec/dependabot/maven/version_spec.rb

@@ -38,11 +38,8 @@
 
     context "with a malformed version string" do
       let(:version_string) { "-" }
-      let(:err_msg) { "Malformed version string #{version_string}" }
 
-      it "raises an exception" do
-        expect { version }.to raise_error(ArgumentError, err_msg)
-      end
+      it { is_expected.to be(false) }
     end
   end
 
@@ -85,21 +82,21 @@
       it { is_expected.to eq("1.0.0_pre1") }
     end
 
-    context "with a null version" do
+    context "with a blank version" do
       let(:version_string) { nil }
-      let(:err_msg) { "Malformed version string #{version_string}" }
+      let(:err_msg) { "Malformed version string - string is nil" }
 
       it "raises an exception" do
-        expect { version }.to raise_error(ArgumentError, err_msg)
+        expect { version }.to raise_error(Dependabot::BadRequirementError, err_msg)
       end
     end
 
     context "with a malformed version string" do
       let(:version_string) { "-" }
-      let(:err_msg) { "Malformed version string #{version_string}" }
+      let(:err_msg) { "Malformed version string - #{version_string}" }
 
       it "raises an exception" do
-        expect { version }.to raise_error(ArgumentError, err_msg)
+        expect { version }.to raise_error(Dependabot::BadRequirementError, err_msg)
       end
     end
   end