Merge changes from topic "elide_empty_variants" into main

* changes:
  Convert sdk mutator to TransitionMutator
  Convert link mutator to TransitionMutator
  Convert version mutator to TransitionMutator
  Convert python_version mutator to TransitionMutator
  Convert rust_libraries and rust_stdlinkage mutators to TransitionMutators

ui/build/paths/config.go

@@ -86,28 +86,28 @@ func GetConfig(name string) PathConfig {
 // This list specifies whether a particular binary from $PATH is allowed to be
 // run during the build. For more documentation, see path_interposer.go .
 var Configuration = map[string]PathConfig{
-	"bash":           Allowed,
-	"diff":           Allowed,
-	"dlv":            Allowed,
-	"expr":           Allowed,
-	"fuser":          Allowed,
-	"gcert":          Allowed,
-	"gcertstatus":    Allowed,
-	"gcloud":         Allowed,
-	"git":            Allowed,
-	"hexdump":        Allowed,
-	"jar":            Allowed,
-	"java":           Allowed,
-	"javap":          Allowed,
-	"lsof":           Allowed,
-	"openssl":        Allowed,
-	"pstree":         Allowed,
-	"rsync":          Allowed,
-	"sh":             Allowed,
-	"stubby":         Allowed,
-	"tr":             Allowed,
-	"unzip":          Allowed,
-	"zip":            Allowed,
+	"bash":        Allowed,
+	"diff":        Allowed,
+	"dlv":         Allowed,
+	"expr":        Allowed,
+	"fuser":       Allowed,
+	"gcert":       Allowed,
+	"gcertstatus": Allowed,
+	"gcloud":      Allowed,
+	"git":         Allowed,
+	"hexdump":     Allowed,
+	"jar":         Allowed,
+	"java":        Allowed,
+	"javap":       Allowed,
+	"lsof":        Allowed,
+	"openssl":     Allowed,
+	"pstree":      Allowed,
+	"rsync":       Allowed,
+	"sh":          Allowed,
+	"stubby":      Allowed,
+	"tr":          Allowed,
+	"unzip":       Allowed,
+	"zip":         Allowed,
 
 	// Host toolchain is removed. In-tree toolchain should be used instead.
 	// GCC also can't find cc1 with this implementation.