fix: Updated yara import error message

- Better to 'pip install -I -r REQUIREMENTS' to
  have the correct yara-python version working
  for all the modules, than having another one
  failing with yara hash & pe modules

misp_modules/modules/expansion/yara_query.py

@@ -3,7 +3,7 @@ import re
 try:
     import yara
 except (OSError, ImportError):
-    print("yara is missing, use 'pip3 install yara' to install it.")
+    print("yara is missing, use 'pip3 install -I -r REQUIREMENTS' from the root of this repository to install it.")
 
 misperrors = {'error': 'Error'}
 moduleinfo = {'version': '1', 'author': 'Christian STUDER',

misp_modules/modules/expansion/yara_syntax_validator.py

@@ -3,7 +3,7 @@ import requests
 try:
     import yara
 except (OSError, ImportError):
-    print("yara is missing, use 'pip3 install yara' to install it.")
+    print("yara is missing, use 'pip3 install -I -r REQUIREMENTS' from the root of this repository to install it.")
 
 misperrors = {'error': 'Error'}
 mispattributes = {'input': ['yara'], 'output': ['text']}