Remove Bazel alwayslink=True (#5376)

This should have no effect for header only libraries as mentioned.

It was previously removed in e509007d but then accidentally added
again in 26cfec34.

Signed-off-by: Jeremy Nimmer <jeremy.nimmer@tri.global>

cmake/scripts/gen_bazel_build_file.cmake

@@ -42,7 +42,6 @@ string(APPEND CONTENT [=[
     ],
     includes = ["include"],
     visibility = ["//visibility:public"],
-    alwayslink = True,
 )
 
 cc_library(