chore: Update charm libraries (#401)

lib/charms/prometheus_k8s/v0/prometheus_scrape.py

@@ -362,7 +362,7 @@ def _on_scrape_targets_changed(self, event):
 
 # Increment this PATCH version before using `charmcraft publish-lib` or reset
 # to 0 if you are raising the major API version
-LIBPATCH = 47
+LIBPATCH = 48
 
 PYDEPS = ["cosl"]
 
@@ -2364,12 +2364,9 @@ def _get_tool_path(self) -> Optional[Path]:
         arch = "amd64" if arch == "x86_64" else arch
         res = "cos-tool-{}".format(arch)
         try:
-            path = Path(res).resolve()
-            path.chmod(0o777)
+            path = Path(res).resolve(strict=True)
             return path
-        except NotImplementedError:
-            logger.debug("System lacks support for chmod")
-        except FileNotFoundError:
+        except (FileNotFoundError, OSError):
             logger.debug('Could not locate cos-tool at: "{}"'.format(res))
         return None