Pass -vv to pip subprocess

Fixes pypa#12577

This looks like it was an oversight in pypa#9450 - we should pass the
correct verbosity level to build env install subprocesses.

Tested with:

```
rm -rf ~/.cache/pip && rm -f *.whl && pip wheel --no-binary :all: hatchling
```

and all three verbosity levels, before and after this change, giving
the following logs:

```
     33 patched-verbosity0.log
   2549 patched-verbosity1.log
  11938 patched-verbosity2.log
     33 unpatched-verbosity0.log
     99 unpatched-verbosity1.log
   1030 unpatched-verbosity2.log
```

i.e. currently a lot of useful logs are being dropped from these install
subprocesess even with -vvv

news/12577.bugfix.rst

@@ -0,0 +1 @@
+Ensure ``-vv`` gets passed to any ``pip install`` build environment subprocesses.

src/pip/_internal/build_env.py

@@ -19,6 +19,7 @@
 from pip._internal.cli.spinners import open_spinner
 from pip._internal.locations import get_platlib, get_purelib, get_scheme
 from pip._internal.metadata import get_default_environment, get_environment
+from pip._internal.utils.logging import VERBOSE
 from pip._internal.utils.subprocess import call_subprocess
 from pip._internal.utils.temp_dir import TempDirectory, tempdir_kinds
 
@@ -242,6 +243,8 @@ def _install_requirements(
  "--no-warn-script-location",
  ]
  if logger.getEffectiveLevel() <= logging.DEBUG:
+ args.append("-vv")
+ elif logger.getEffectiveLevel() <= VERBOSE:
  args.append("-v")
  for format_control in ("no_binary", "only_binary"):
  formats = getattr(finder.format_control, format_control)