Update shebang reference names

This updates the rule names for shebang which were changed in
rust-lang/reference#2192 and
rust-lang/reference#2199.

Author: ehuss

tests/ui/parser/shebang/multiline-attrib.rs

@@ -1,7 +1,7 @@
 #!
 [allow(unused_variables)]
 //@ check-pass
-//@ reference: input.shebang.inner-attribute
+//@ reference: shebang.syntax-description
 
 fn main() {
     let x = 5;

tests/ui/parser/shebang/regular-attrib.rs

@@ -1,6 +1,6 @@
 #![allow(unused_variables)]
 //@ check-pass
-//@ reference: input.shebang.inner-attribute
+//@ reference: shebang.syntax-description
 fn main() {
     let x = 5;
 }

tests/ui/parser/shebang/shebang-and-attrib.rs

@@ -1,7 +1,7 @@
 #!/usr/bin/env run-cargo-script
 
 //@ check-pass
-//@ reference: input.shebang.inner-attribute
+//@ reference: shebang.syntax-description
 #![allow(unused_variables)]
 
 

tests/ui/parser/shebang/shebang-doc-comment.rs

@@ -2,4 +2,4 @@
 [allow(unused_variables)]
 //~^ ERROR expected item, found `[`
 
-//@ reference: input.shebang.inner-attribute
+//@ reference: shebang.syntax-description

tests/ui/parser/shebang/sneaky-attrib.rs

@@ -11,7 +11,7 @@
 [allow(unused_variables)]
 
 //@ check-pass
-//@ reference: input.shebang.inner-attribute
+//@ reference: shebang.syntax-description
 fn main() {
     let x = 5;
 }