Small fixes to build files and readme

* Remove duplicate https://
* Update test library to use @gtest//:gtest instead of gtest_main
* Declare hdrs in astc_codec library.
diff --git a/BUILD.bazel b/BUILD.bazel
index 8fc9eca..ea5a2c4 100644
--- a/BUILD.bazel
+++ b/BUILD.bazel
@@ -22,7 +22,8 @@
 
 cc_library(
     name = "astc_codec",
-    deps = ["//src/decoder:codec"],
+    hdrs = ["include/astc-codec/astc-codec.h"],
     includes = ["include"],
     visibility = ["//visibility:public"],
+    deps = ["//src/decoder:codec"],
 )
diff --git a/README.md b/README.md
index 8bb2c26..55daaa6 100644
--- a/README.md
+++ b/README.md
@@ -42,7 +42,7 @@
 
 ### With CMake
 
-Install [CMake](https://https://cmake.org/), and the run:
+Install [CMake](https://cmake.org/), and the run:
 
 ```
 mkdir build && cd build && cmake .. && make
diff --git a/src/decoder/BUILD.bazel b/src/decoder/BUILD.bazel
index 2ff0ead..ccc764e 100644
--- a/src/decoder/BUILD.bazel
+++ b/src/decoder/BUILD.bazel
@@ -90,7 +90,7 @@
     name = "test",
     testonly = 1,
     hdrs = ["test/image_utils.h"],
-    deps = ["@gtest//:gtest_main"],
+    deps = ["@gtest//:gtest"],
 )
 
 cc_test(