Pin various python libs and fix branch in build.lock

The python lib pins are for py35 compatability.  The branch issue is due
to bug juju/charm-tools#604

* Also add cffi pin for py35 for charm-tools build support.

Change-Id: I2ac189816b1e133ff8468d4722ce87da48b85c0b

requirements.txt

@@ -9,6 +9,7 @@
 setuptools<50.0.0  # https://github.com/pypa/setuptools/commit/04e3df22df840c6bb244e9b27bc56750c44b7c85
 
 # Build requirements
+cffi==1.14.6; python_version < '3.6'  # cffi 1.15.0 drops support for py35.
 charm-tools==2.8.3
 
 simplejson

src/build.lock

@@ -101,7 +101,7 @@
       "item": "interface:ceph-client",
       "url": "https://opendev.org/openstack/charm-interface-ceph-client.git",
       "vcs": null,
-      "branch": null,
+      "branch": "3ca251fb01a7cd51d2a0ee2b9b66647c8ffe891f",
       "commit": "3ca251fb01a7cd51d2a0ee2b9b66647c8ffe891f"
     },
     {
@@ -172,7 +172,7 @@
       "type": "python_module",
       "package": "botocore",
       "vcs": null,
-      "version": "1.21.58"
+      "version": "1.19.63"
     },
     {
       "type": "python_module",
@@ -184,7 +184,7 @@
       "type": "python_module",
       "package": "s3transfer",
       "vcs": null,
-      "version": "0.5.0"
+      "version": "0.3.6"
     },
     {
       "type": "python_module",
@@ -222,7 +222,7 @@
       "type": "python_module",
       "package": "boto3",
       "vcs": null,
-      "version": "1.18.58"
+      "version": "1.16.63"
     },
     {
       "type": "python_module",
@@ -269,4 +269,4 @@
       "version": "1.26.7"
     }
   ]
-}
+}

src/wheelhouse.txt

@@ -1,4 +1,4 @@
-boto3
+boto3<1.17.0  # pin for py35 compatability
 
 git+https://github.com/openstack/charms.openstack.git@stable/21.10#egg=charms.openstack