Do not hang when deciding not to compress a file upload

This command would hang forever:

```console
$ echo test > test.txt
$ http -x httpbin.org/post @test.txt
```

HTTPie would read the file, compress it, then discard the compressed
data because it's larger than the original. This made `request.body`
an exhausted file handle, which `requests` doesn't seem to like.

httpie/uploads.py

@@ -258,6 +258,9 @@ def compress_request(
         body_bytes = request.body.encode()
     elif hasattr(request.body, 'read'):
         body_bytes = request.body.read()
+        # The body is consumed now, so if we don't end up compressing we should
+        # use the bytes we just read
+        request.body = body_bytes
     else:
         body_bytes = request.body
     deflated_data = deflater.compress(body_bytes)

tests/fixtures/__init__.py

@@ -22,6 +22,7 @@ def patharg(path):
 JSON_FILE_PATH = FIXTURES_ROOT / 'test.json'
 JSON_WITH_DUPE_KEYS_FILE_PATH = FIXTURES_ROOT / 'test_with_dupe_keys.json'
 BIN_FILE_PATH = FIXTURES_ROOT / 'test.bin'
+TINY_FILE_PATH = FIXTURES_ROOT / 'test_tiny.txt'
 
 XML_FILES_PATH = FIXTURES_ROOT / 'xmldata'
 XML_FILES_VALID = list((XML_FILES_PATH / 'valid').glob('*_raw.xml'))
@@ -39,6 +40,7 @@ def patharg(path):
 FILE_PATH_ARG = patharg(FILE_PATH)
 BIN_FILE_PATH_ARG = patharg(BIN_FILE_PATH)
 JSON_FILE_PATH_ARG = patharg(JSON_FILE_PATH)
+TINY_FILE_PATH_ARG = patharg(TINY_FILE_PATH)
 
 # Strip because we don't want new lines in the data so that we can
 # easily count occurrences also when embedded in JSON (where the new

tests/fixtures/test_tiny.txt

@@ -0,0 +1 @@
+test

tests/test_compress.py

@@ -11,7 +11,7 @@
 import base64
 import zlib
 
-from .fixtures import FILE_PATH, FILE_CONTENT
+from .fixtures import FILE_PATH, FILE_CONTENT, TINY_FILE_PATH_ARG
 from httpie.status import ExitStatus
 from .utils import StdinBytesIO, http, HTTP_OK, MockEnvironment
 
@@ -138,3 +138,16 @@ def test_compress_file(httpbin_both):
         'multipart/form-data; boundary=')
     assert r.json['files'] == {}
     assert FILE_CONTENT not in r
+
+
+def test_compress_skip_negative_ratio_file_upload(httpbin):
+    """Reading the upload body but not compressing it doesn't cause a hang."""
+    r = http(
+        '--compress',
+        'PUT',
+        httpbin + '/put',
+        f'@{TINY_FILE_PATH_ARG}',
+    )
+    assert HTTP_OK in r
+    assert 'Content-Encoding' not in r.json['headers']
+    assert r.json['data'] == 'test\n'