Add v2_20_1 arrays to backward compatibility matrix. (#4770)

TYPE: NO_HISTORY

Author: bekadavis9

.github/workflows/build-ubuntu20.04-backwards-compatibility.yml

@@ -59,7 +59,7 @@ jobs:
           - ubuntu-20.04
         # Note: v2_1_0 arrays were never created so its currently skipped
         # Note: This matrix is used to set the value of TILEDB_COMPATIBILITY_VERSION
-        tiledb_version: ["v1_4_0", "v1_5_0", "v1_6_0", "v1_7_0", "v2_0_0", "v2_2_0", "v2_2_3", "v2_3_0", "v2_4_0", "v2_5_0", "v2_6_0", "v2_7_0", "v2_8_3", "v2_9_1", "v2_10_0", "v2_11_0", "v2_12_3", "v2_13_2", "v2_14_0", "v2_15_0", "v2_16_3", "v2_17_5", "v2_18_3", "v2_19_1"]
+        tiledb_version: ["v1_4_0", "v1_5_0", "v1_6_0", "v1_7_0", "v2_0_0", "v2_2_0", "v2_2_3", "v2_3_0", "v2_4_0", "v2_5_0", "v2_6_0", "v2_7_0", "v2_8_3", "v2_9_1", "v2_10_0", "v2_11_0", "v2_12_3", "v2_13_2", "v2_14_0", "v2_15_0", "v2_16_3", "v2_17_5", "v2_18_3", "v2_19_1", "v2_20_1"]
     timeout-minutes: 30
     name: ${{ matrix.tiledb_version }}
     steps: