test(core): share MAINNET_BLOCK_1_HEX between block hash display tests

Reuses the constant introduced for the Block::check tests, removing
the duplicated inline hex from test_block_hash_display and
test_block_hash_ref_display.

Author: pzafonte

src/core/block.rs

@@ -2326,19 +2326,7 @@ mod tests {
 
     #[test]
     fn test_block_hash_display() {
-        let block = Block::new(
-            hex::decode(
-                "010000006fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000000000982051fd\
-                1e4ba744bbbe680e1fee14677ba1a3c3540bf7b1cdb606e857233e0e61bc6649ffff001d01e36299\
-                0101000000010000000000000000000000000000000000000000000000000000000000000000ffff\
-                ffff0704ffff001d0104ffffffff0100f2052a0100000043410496b538e853519c726a2c91e61ec1\
-                1600ae1390813a627c66fb8be7947be63c52da7589379515d4e0a604f8141781e62294721166bf62\
-                1e73a82cbf2342c858eeac00000000",
-            )
-            .unwrap()
-            .as_slice(),
-        )
-        .unwrap();
+        let block = Block::new(hex::decode(MAINNET_BLOCK_1_HEX).unwrap().as_slice()).unwrap();
 
         let block_hash = block.hash().to_owned();
 
@@ -2350,19 +2338,7 @@ mod tests {
 
     #[test]
     fn test_block_hash_ref_display() {
-        let block = Block::new(
-            hex::decode(
-                "010000006fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000000000982051fd\
-                1e4ba744bbbe680e1fee14677ba1a3c3540bf7b1cdb606e857233e0e61bc6649ffff001d01e36299\
-                0101000000010000000000000000000000000000000000000000000000000000000000000000ffff\
-                ffff0704ffff001d0104ffffffff0100f2052a0100000043410496b538e853519c726a2c91e61ec1\
-                1600ae1390813a627c66fb8be7947be63c52da7589379515d4e0a604f8141781e62294721166bf62\
-                1e73a82cbf2342c858eeac00000000",
-            )
-            .unwrap()
-            .as_slice(),
-        )
-        .unwrap();
+        let block = Block::new(hex::decode(MAINNET_BLOCK_1_HEX).unwrap().as_slice()).unwrap();
 
         let block_hash_ref = block.hash();