chore(asm): migrate appsec capabilities to drop python2 compatibility (#7135)

drop python 2 and `ddtrace.internal.compat` dependency in
`appsec/_capabilities.py`
simplify some imports
follows #7121

## Checklist

- [x] Change(s) are motivated and described in the PR description.
- [x] Testing strategy is described if automated tests are not included
in the PR.
- [x] Risk is outlined (performance impact, potential for breakage,
maintainability, etc).
- [x] Change is maintainable (easy to change, telemetry, documentation).
- [x] [Library release note
guidelines](https://ddtrace.readthedocs.io/en/stable/releasenotes.html)
are followed. If no release note is required, add label
`changelog/no-changelog`.
- [x] Documentation is included (in-code, generated user docs, [public
corp docs](https://github.com/DataDog/documentation/)).
- [x] Backport labels are set (if
[applicable](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting))

## Reviewer Checklist

- [ ] Title is accurate.
- [ ] No unnecessary changes are introduced.
- [ ] Description motivates each change.
- [ ] Avoids breaking
[API](https://ddtrace.readthedocs.io/en/stable/versioning.html#interfaces)
changes unless absolutely necessary.
- [ ] Testing strategy adequately addresses listed risk(s).
- [ ] Change is maintainable (easy to change, telemetry, documentation).
- [ ] Release note makes sense to a user of the library.
- [ ] Reviewer has explicitly acknowledged and discussed the performance
implications of this PR as reported in the benchmarks PR comment.
- [ ] Backport labels are set in a manner that is consistent with the
[release branch maintenance
policy](https://ddtrace.readthedocs.io/en/latest/contributing.html#backporting)
- [ ] If this PR touches code that signs or publishes builds or
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- [ ] This PR doesn't touch any of that.

Author: christophe-papazian

ddtrace/appsec/_capabilities.py

@@ -1,20 +1,16 @@
 import base64
 import os
-import sys
 from typing import Optional
 
-from ddtrace import Tracer
-from ddtrace import config as ddconfig
+import ddtrace
 from ddtrace.appsec._utils import _appsec_rc_features_is_enabled
-from ddtrace.internal.compat import to_bytes_py2
 
 
 def _appsec_rc_file_is_not_static():
     return "DD_APPSEC_RULES" not in os.environ
 
 
-def _appsec_rc_capabilities(test_tracer=None):
-    # type: (Optional[Tracer]) -> str
+def _appsec_rc_capabilities(test_tracer: Optional[ddtrace.Tracer] = None) -> str:
     r"""return the bit representation of the composed capabilities in base64
     bit 0: Reserved
     bit 1: ASM 1-click Activation
@@ -30,14 +26,10 @@ def _appsec_rc_capabilities(test_tracer=None):
     ...
     256         -> 100000000        -> b'\x01\x00'          -> b'AQA='
     """
-    if test_tracer is None:
-        from ddtrace import tracer
-    else:
-        tracer = test_tracer
-
+    tracer = ddtrace.tracer if test_tracer is None else test_tracer
     value = 0b0
     result = ""
-    if ddconfig._remote_config_enabled:
+    if ddtrace.config._remote_config_enabled:
         if _appsec_rc_features_is_enabled():
             value |= 1 << 1  # Enable ASM_ACTIVATION
         if tracer._appsec_processor and _appsec_rc_file_is_not_static():
@@ -50,12 +42,5 @@ def _appsec_rc_capabilities(test_tracer=None):
             value |= 1 << 8  # Enable ASM_CUSTOM_RULES
             value |= 1 << 9  # Enable ASM_CUSTOM_BLOCKING_RESPONSE
             value |= 1 << 10  # Enable ASM_TRUSTED_IPS
-
-        if sys.version_info.major < 3:
-            bytes_res = to_bytes_py2(value, (value.bit_length() + 7) // 8, "big")
-            # "type: ignore" because mypy does not notice this is for Python2 b64encode
-            result = str(base64.b64encode(bytes_res))  # type: ignore
-        else:
-            result = str(base64.b64encode(value.to_bytes((value.bit_length() + 7) // 8, "big")), encoding="utf-8")
-
+        result = base64.b64encode(value.to_bytes((value.bit_length() + 7) // 8, "big")).decode()
     return result