tox: Only install pip as dep when needed

misc/eslint don't actually install anything, so no point in updating pip
there.

pyroma/check-manifest should install pip though.

tox.ini

@@ -75,7 +75,7 @@ ignore_errors = true
 basepython = python3
 # For global .gitignore files
 passenv = HOME
-deps = -r{toxinidir}/misc/requirements/requirements-pip.txt
+deps =
 commands =
     {envpython} scripts/dev/misc_checks.py git
     {envpython} scripts/dev/misc_checks.py vcs
@@ -125,14 +125,18 @@ commands =
 [testenv:pyroma]
 basepython = python3
 passenv =
-deps = -r{toxinidir}/misc/requirements/requirements-pyroma.txt
+deps =
+    -r{toxinidir}/misc/requirements/requirements-pip.txt
+    -r{toxinidir}/misc/requirements/requirements-pyroma.txt
 commands =
     {envdir}/bin/pyroma .
 
 [testenv:check-manifest]
 basepython = python3
 passenv =
-deps = -r{toxinidir}/misc/requirements/requirements-check-manifest.txt
+deps =
+    -r{toxinidir}/misc/requirements/requirements-pip.txt
+     -r{toxinidir}/misc/requirements/requirements-check-manifest.txt
 commands =
     {envdir}/bin/check-manifest --ignore 'qutebrowser/git-commit-id,qutebrowser/html/doc,qutebrowser/html/doc/*,*/__pycache__'
 
@@ -173,5 +177,6 @@ commands =
     {envbindir}/pyinstaller --noconfirm misc/qutebrowser.spec
 
 [testenv:eslint]
+deps =
 whitelist_externals = eslint
 commands = eslint --color qutebrowser/javascript