fix: only consider major when commit message starts with major identifier

Author: CallMeLeopoldo

spec/git-version-spec.cr

@@ -474,7 +474,7 @@ describe GitVersion do
       tmp.exec %(git checkout -b master)
       tmp.exec %(git commit --no-gpg-sign --allow-empty -m "1")
       tmp.exec %(git tag "0.1.0")
-      tmp.exec %(git commit --no-gpg-sign --allow-empty -m ":breaking: 2")
+      tmp.exec %(git commit --no-gpg-sign --allow-empty -m "breaking: 2")
 
       version = git.get_new_version
       version.should eq("1.0.0")
@@ -495,7 +495,7 @@ describe GitVersion do
       tmp.exec %(git tag "0.1.0")
       tmp.exec %(git commit --no-gpg-sign --allow-empty -m "feature: 2")
       tmp.exec %(git tag "0.2.0-asd")
-      tmp.exec %(git commit --no-gpg-sign --allow-empty -m ":breaking: 2")
+      tmp.exec %(git commit --no-gpg-sign --allow-empty -m "breaking: 2")
 
       version = git.get_new_version
       version.should eq("1.0.0")

src/git-version.cr

@@ -153,9 +153,9 @@ module GitVersion
       get_commits_since(previous_tag).each do |c|
         commit = c.downcase
         match = if @major_id_is_regex
-          /#{@major_identifier}/.match(commit)
+          /^#{@major_identifier}/.match(commit)
         else
-          commit.includes?(@major_identifier)
+          /^#{@major_identifier}/.match(commit)
         end
         if match
           previous_version =