docker: fix the core lightning build

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 > [ 7/11] RUN git config --global user.name "John Doe" && 	git config --global user.email [email protected] && 	git clone https://github.com/ElementsProject/lightning.git &&     cd lightning &&     poetry config virtualenvs.create false &&     poetry install &&     ./configure &&     make -j$(nproc):
12.23       352│                 )
12.23       353│         except CalledProcessError as e:
12.23     → 354│             raise EnvCommandError(e)
12.23       355│
12.23       356│         return output
12.23       357│
12.23       358│     def execute(self, bin: str, *args: str, **kwargs: Any) -> int:
12.23
12.23 Cannot install blinker.
12.23
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Dockerfile.clightning:58
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  57 |
  58 | >>> RUN git config --global user.name "John Doe" && \
  59 | >>> 	git config --global user.email [email protected] && \
  60 | >>> 	git clone https://github.com/ElementsProject/lightning.git && \
  61 | >>>     cd lightning && \
  62 | >>>     poetry config virtualenvs.create false && \
  63 | >>>     poetry install && \
  64 | >>>     ./configure && \
  65 | >>>     make -j$(nproc)
  66 |
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ERROR: failed to solve: process "/bin/sh -c git config --global user.name \"John Doe\" && \tgit config --global user.email [email protected] && \tgit clone https://github.com/ElementsProject/lightning.git &&     cd lightning &&     poetry config virtualenvs.create false &&     poetry install &&     ./configure &&     make -j$(nproc)" did not complete successfully: exit code: 1

Signed-off-by: Vincenzo Palazzo <[email protected]>

docker/Dockerfile.clightning

@@ -59,8 +59,7 @@ RUN git config --global user.name "John Doe" && \
 	git config --global user.email [email protected] && \
 	git clone https://github.com/ElementsProject/lightning.git && \
     cd lightning && \
-    poetry config virtualenvs.create false && \
-    poetry install && \
+    pip3 install mako && \
     ./configure && \
     make -j$(nproc)