Empty path generates empty short ref (#868)

## Description

Fixup corner case on ShortRef so that empty paths generate the empty string. This makes some cases with generating short refs for each parent path to an item easier because the base case (empty path) is no different than other cases.

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## Type of change

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- [ ] 🌻 Feature
- [x] 🐛 Bugfix
- [ ] 🗺️ Documentation
- [ ] 🤖 Test
- [ ] 💻 CI/Deployment
- [ ] 🐹 Trivial/Minor

## Issue(s)

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* part of #818 

## Test Plan

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- [ ] 💪 Manual
- [x] ⚡ Unit test
- [ ] 💚 E2E

src/internal/path/path.go

@@ -198,6 +198,10 @@ func (pb Builder) String() string {
 }
 
 func (pb Builder) ShortRef() string {
+	if len(pb.elements) == 0 {
+		return ""
+	}
+
 	data := bytes.Buffer{}
 
 	for _, element := range pb.elements {

src/internal/path/path_test.go

@@ -366,9 +366,29 @@ func (suite *PathUnitSuite) TestPopFront() {
 }
 
 func (suite *PathUnitSuite) TestShortRef() {
-	pb := Builder{}.Append("this", "is", "a", "path")
-	ref := pb.ShortRef()
-	assert.Len(suite.T(), ref, shortRefCharacters)
+	table := []struct {
+		name          string
+		inputElements []string
+		expectedLen   int
+	}{
+		{
+			name:          "PopulatedPath",
+			inputElements: []string{"this", "is", "a", "path"},
+			expectedLen:   shortRefCharacters,
+		},
+		{
+			name:          "EmptyPath",
+			inputElements: nil,
+			expectedLen:   0,
+		},
+	}
+	for _, test := range table {
+		suite.T().Run(test.name, func(t *testing.T) {
+			pb := Builder{}.Append(test.inputElements...)
+			ref := pb.ShortRef()
+			assert.Len(suite.T(), ref, test.expectedLen)
+		})
+	}
 }
 
 func (suite *PathUnitSuite) TestShortRefIsStable() {