Allow running AMQP 1.0 client test suite with make

Prior to this commit:
```
make -C deps/amqp10_client/ ct-system t=rabbitmq:open_close_connection FULL=1
mock_server.erl:19:10: can't find include file "amqp10_client.hrl"
```

After this commit, both
```
make -C deps/amqp10_client/ ct-system t=rabbitmq:open_close_connection FULL=1
```
and
```
bazel test //deps/amqp10_client:system_SUITE --test_env FOCUS="-group rabbitmq -case open_close_connection"
```
succeed.

Author: ansd

deps/amqp10_client/test/mock_server.erl

@@ -16,7 +16,7 @@
          recv_amqp_header_step/1
         ]).
 
--include("amqp10_client.hrl").
+-include("src/amqp10_client.hrl").
 
 start(Port) ->
     {ok, LSock} = gen_tcp:listen(Port, [binary, {packet, 0}, {active, false}]),

deps/amqp10_client/test/system_SUITE.erl

@@ -12,7 +12,7 @@
 
 -include_lib("amqp10_common/include/amqp10_framing.hrl").
 
--include("amqp10_client.hrl").
+-include("src/amqp10_client.hrl").
 
 -compile(export_all).