Exporting MakeBazelTarget() in testing.go

Since we are putting conversion tests in the same
package as the module being converted from now on

Test: m bp2build
Change-Id: Ied53589d497fef70bfa11d8f6067459c9a50cd72
diff --git a/bp2build/prebuilt_etc_conversion_test.go b/bp2build/prebuilt_etc_conversion_test.go
index fce4c74..6738b4b 100644
--- a/bp2build/prebuilt_etc_conversion_test.go
+++ b/bp2build/prebuilt_etc_conversion_test.go
@@ -45,7 +45,7 @@
 }
 `,
 		ExpectedBazelTargets: []string{
-			makeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
+			MakeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
 				"filename":    `"tz_version"`,
 				"installable": `False`,
 				"src":         `"version/tz_version"`,
@@ -75,7 +75,7 @@
 }
 `,
 		ExpectedBazelTargets: []string{
-			makeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
+			MakeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
 				"filename":    `"tz_version"`,
 				"installable": `False`,
 				"src": `select({
@@ -114,7 +114,7 @@
 }
 `,
 		ExpectedBazelTargets: []string{
-			makeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
+			MakeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
 				"filename":    `"tz_version"`,
 				"installable": `False`,
 				"src": `select({
@@ -153,7 +153,7 @@
 }
 `,
 		ExpectedBazelTargets: []string{
-			makeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
+			MakeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
 				"filename":    `"tz_version"`,
 				"installable": `False`,
 				"src":         `"version/tz_version"`,
@@ -174,7 +174,7 @@
 }
 `,
 		ExpectedBazelTargets: []string{
-			makeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
+			MakeBazelTarget("prebuilt_file", "apex_tz_version", AttrNameToString{
 				"filename":    `"tz_version"`,
 				"installable": `False`,
 				"src":         `"version/tz_version"`,