t/Makefile: build git-lfs-test-server-api as part of integration tests

We want to be sure this test script gets built regularly to avoid
breakage during refactors.  In order to do so, build it as part of the
integration test suite.

Author: bk2204

t/Makefile

@@ -19,7 +19,12 @@ TEST_CMDS += ../bin/lfstest-gitserver$X
 TEST_CMDS += ../bin/lfstest-standalonecustomadapter$X
 TEST_CMDS += ../bin/lfstest-testutils$X
 
-TEST_SRCS = $(wildcard t-*.sh)
+# Not used for the integration tests, but build it here anyway to ensure it
+# continues to work.
+TEST_CMDS += ../bin/git-lfs-test-server-api$X
+
+TEST_SRCS     = $(wildcard t-*.sh)
+TEST_API_SRCS = $(wildcard git-lfs-test-server-api/*.go)
 
 all : $(DEFAULT_TEST_TARGET)
 
@@ -41,3 +46,6 @@ clean :
 
 ../bin/%$X : cmd/%.go
 	go build -o $@ $^
+
+../bin/git-lfs-test-server-api$X : $(TEST_API_SRCS)
+	go build -o $@ $^